FINAL TEST AT LABORATORY
Study of the diffusion in gaseous state and molecular speeds
Do not use this paper to give answers!
Please decide which of the following statements are true.- The position of the ring in the experiment is dependent on:
- the propagation of the species as ions and not as neutral molecules;
- the virtual speeds and not the real speeds of each involved species;
- the width of the tube and not of the length of the tube;
- the mode energy or mode speed of each involved species;
- The time to the formation of the ring in the experiment is dependent on:
- the virtual speeds and not the real speeds of each involved species;
- the speed of diffusion of each involved species;
- the length of the tube and the width of the tube;
- the propagation of the species as neutral molecules and not as ions;
- The chronometer is used in the experiment for:
- extracting the information necessary to calculate the speeds ratio;
- synchronization of the diffusion times;
- to keep us busy;
- indication of the moment when we should pay attention to the experiment;
- We may say the followings:
- the molecules have speeds only in gaseous and liquid states;
- the molecules have energy only in gaseous and liquid states;
- the molecules have energy only in gaseous state;
- the molecules have speeds only in gaseous state;
- At the ends of the tube following equilibrium reactions occurs:
- NH4+ + Cl- \=\ NH4Cl
- HCl + H2O \=\ Cl- + H3O+
- H+ + HO- \=\ H2O
- NH3 + HCl \=\ NH4Cl
TEST DE FINAL DE LABORATOR
Studiul difuziei in stare gazoasa si a vitezelor moleculare
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Pozitia inelului īn experimentul este dependenta de:
- propagarea speciilor ca ionii si nu ca si molecule neutre;
- vitezele virtuale si nu vitezele reale ale fiecarei specii implicate;
- latimea tubului si nu lungimea tubului;
- viteza la moda sau energia la moda a fiecarei specii implicate;
- lungimea tubului si nu latimea tubului;
- Timpul pentru formarea inelului īn experimentul este dependenta de:
- vitezele virtuale si nu vitezele reale ale fiecarei specii implicate;
- viteza de difuzie a fiecarei specii implicate;
- lungimea tubului si latimea tubului;
- propagarea speciilor ca si molecule neutre si nu ca si ioni;
- concentratiile solutiilor utilizate;
- Cronometrul este utilizat īn experimentul pentru:
- extragerea informatiilor necesare pentru calcularea raportului vitezelor;
- sincronizarea timpilor de difuzie;
- sa ne tina ocupati;
- indicarea momentului cānd trebuie sa se acorde atentie experimentului;
- extragerea informatiilor necesare pentru a calcula coeficientii de difuzie;
- Va rugam sa decida cu adevarat / fals pentru urmatoarele afirmatii:
- moleculele au viteze numai īn stare gazoasa si lichida;
- moleculele au energie numai īn stare gazoasa si lichida;
- moleculele au energie numai īn stare gazoasa;
- moleculele au viteze numai īn stare gazoasa;
- La capetele tubului urmatoarele reactii de echilibru apar:
- NH4+ + Cl- \=\ NH4Cl
- HCl + H2O \=\ Cl- + H3O+
- H+ + HO- \=\ H2O
- NH3 + HCl \=\ NH4Cl
FINAL TEST AT LABORATORY
Study of the diffusion in gaseous state and molecular speeds
Do not use this paper to give answers!
Please decide which of the following statements are true.- The chronometer is used in the experiment for:
- to keep us busy;
- extracting the information necessary to calculate the diffusion coefficients;
- measuring of the diffusion time;
- synchronization of the diffusion times;
- As you concluded from the experiment, the molecules of a gas at equilibrium:
- all are moving in an arbitrary direction;
- are considered to be at the same temperature, but may have different speeds;
- all are moving in the same direction;
- all have same speed;
- We may say the followings:
- the molecules have speeds only in gaseous state;
- the molecules have energy only in gaseous state;
- the molecules have speeds only in gaseous and liquid states;
- the molecules have energy only in gaseous and liquid states;
- The position of the ring in the experiment is dependent on:
- the average energy or average speed of each involved species;
- the speed of diffusion of each involved species;
- the length of the tube and the width of the tube;
- the real speeds and not the virtual speeds of each involved species;
- The fog observed during the experiment is due to:
- unproper illumination in the laboratory or our breathing;
- our experiment designed to trap the product of the reaction;
- presence of the ammonia;
- presence of the chlorine;
TEST DE FINAL DE LABORATOR
Studiul difuziei in stare gazoasa si a vitezelor moleculare
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Cronometrul este utilizat īn experimentul pentru:
- sa ne tina ocupati;
- extragerea informatiilor necesare pentru a calcula coeficientii de difuzie;
- masurarea timpului de difuzie;
- sincronizarea timpilor de difuzie;
- indicarea momentului cānd trebuie sa se acorde atentie experimentului;
- Asa cum s-a concluzionat din experiment, moleculele unui gaz la echilibru:
- toate se īndreapta īntr-o directie arbitrara;
- sunt considerate a fi la aceeasi temperatura, dar pot avea viteze diferite;
- toate se deplaseaza īn aceeasi directie;
- toate au aceeasi viteza;
- toate au aceeasi energie;
- Va rugam sa decida cu adevarat / fals pentru urmatoarele afirmatii:
- moleculele au viteze numai īn stare gazoasa;
- moleculele au energie numai īn stare gazoasa;
- moleculele au viteze numai īn stare gazoasa si lichida;
- moleculele au energie numai īn stare gazoasa si lichida;
- energia cinetica a unei molecule este afectata de temperatura si presiune;
- Pozitia inelului īn experimentul este dependenta de:
- energia medie sau viteza medie a fiecarei specii implicate;
- viteza de difuzie a fiecarei specii implicate;
- lungimea tubului si latimea tubului;
- vitezele reale si nu vitezele virtuale ale fiecarei specii implicate;
- Ceata observata īn timpul experimentului se datoreaza:
- iluminarii necorespunzatoare īn laborator sau respiratie noastre;
- experimentului nostru proiectat pentru a captura produsul de reactie;
- prezentei amoniacului;
- prezentei clorului;
FINAL TEST AT LABORATORY
Study of the diffusion in gaseous state and molecular speeds
Do not use this paper to give answers!
Please decide which of the following statements are true.- We may say the followings:
- diffusion process appears in all gaseous, liquid and solid states;
- the molecules have energy only in gaseous and liquid states;
- the molecules have energy in all gaseous, liquid and solid states;
- diffusion process appears only in gaseous and liquid states;
- As you concluded from the experiment, the molecules of a gas at equilibrium:
- all have same energy;
- all are moving in the same direction;
- are considered to be at the same temperature, but may have different energies;
- all have same speed;
- The position of the ring in the experiment is dependent on:
- the virtual speeds and not the real speeds of each involved species;
- the length of the tube and not of the width of the tube;
- the concentrations of the solutions used;
- the propagation of the species as ions and not as neutral molecules;
- The time to the formation of the ring in the experiment is dependent on:
- the length of the tube and not of the width of the tube;
- the length of the tube and the width of the tube;
- the virtual speeds and not the real speeds of each involved species;
- the speed of diffusion of each involved species;
- At the ends of the tube following equilibrium reactions occurs:
- NH3 + HCl \=\ NH4Cl
- H2O \=\ H+ + HO-
- H+ + HO- \=\ H2O
- NH4+ + Cl- \=\ NH4Cl
TEST DE FINAL DE LABORATOR
Studiul difuziei in stare gazoasa si a vitezelor moleculare
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Va rugam sa decida cu adevarat / fals pentru urmatoarele afirmatii:
- proces de difuzie apare īn toate starile gazoasa, lichida si solida;
- moleculele au energie numai īn stare gazoasa si lichida;
- moleculele au energie īn toate starile gazoasa, lichida si solida;
- proces de difuzie apare numai īn stare gazoasa si lichida;
- Asa cum s-a concluzionat din experiment, moleculele unui gaz la echilibru:
- toate au aceeasi energie;
- toate se deplaseaza īn aceeasi directie;
- sunt considerate a fi la aceeasi temperatura, dar pot avea diferite energii;
- toate au aceeasi viteza;
- toate se īndreapta īntr-o directie arbitrara;
- Pozitia inelului īn experimentul este dependenta de:
- vitezele virtuale si nu vitezele reale ale fiecarei specii implicate;
- lungimea tubului si nu latimea tubului;
- concentratiile solutiilor utilizate;
- propagarea speciilor ca ionii si nu ca si molecule neutre;
- Timpul pentru formarea inelului īn experimentul este dependenta de:
- lungimea tubului si nu latimea tubului;
- lungimea tubului si latimea tubului;
- vitezele virtuale si nu vitezele reale ale fiecarei specii implicate;
- viteza de difuzie a fiecarei specii implicate;
- energia medie sau viteza medie a fiecarei specii implicate;
- La capetele tubului urmatoarele reactii de echilibru apar:
- NH3 + HCl \=\ NH4Cl
- H2O \=\ H+ + HO-
- H+ + HO- \=\ H2O
- NH4+ + Cl- \=\ NH4Cl
- NH3 + H2O \ = \ NH4+ + HO-
FINAL TEST AT LABORATORY
Study of the diffusion in gaseous state and molecular speeds
Do not use this paper to give answers!
Please decide which of the following statements are true.- The fog observed during the experiment is due to:
- formation of ammonium chloride;
- unproper illumination in the laboratory or our breathing;
- presence of the chlorine;
- presence of the ammonia;
- At the ends of the tube following equilibrium reactions occurs:
- NH3 + H2O \=\ NH4+ + HO-
- NH3 + HCl \=\ NH4Cl
- H2O \=\ H+ + HO-
- HCl + H2O \=\ Cl- + H3O+
- The position of the ring in the experiment is dependent on:
- the length of the tube and the width of the tube;
- the length of the tube and not of the width of the tube;
- the concentrations of the solutions used;
- the width of the tube and not of the length of the tube;
- The chronometer is used in the experiment for:
- measuring of the diffusion time;
- extracting the information necessary to calculate the speeds ratio;
- extracting the information necessary to calculate the diffusion coefficients;
- to keep us busy;
- As you concluded from the experiment, the molecules of a gas at equilibrium:
- are considered to be at the same temperature, but may have different energies;
- all have same speed;
- all are moving in the same direction;
- are considered to be at the same temperature, but may have different speeds;
TEST DE FINAL DE LABORATOR
Studiul difuziei in stare gazoasa si a vitezelor moleculare
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Ceata observata īn timpul experimentului se datoreaza:
- formarea clorurii de amoniu;
- iluminarii necorespunzatoare īn laborator sau respiratie noastre;
- prezentei clorului;
- prezentei amoniacului;
- La capetele tubului urmatoarele reactii de echilibru apar:
- NH3 + H2O \ = \ NH4+ + HO-
- NH3 + HCl \=\ NH4Cl
- H2O \=\ H+ + HO-
- HCl + H2O \=\ Cl- + H3O+
- Pozitia inelului īn experimentul este dependenta de:
- lungimea tubului si latimea tubului;
- lungimea tubului si nu latimea tubului;
- concentratiile solutiilor utilizate;
- latimea tubului si nu lungimea tubului;
- vitezele reale si nu vitezele virtuale ale fiecarei specii implicate;
- Cronometrul este utilizat īn experimentul pentru:
- masurarea timpului de difuzie;
- extragerea informatiilor necesare pentru calcularea raportului vitezelor;
- extragerea informatiilor necesare pentru a calcula coeficientii de difuzie;
- sa ne tina ocupati;
- Asa cum s-a concluzionat din experiment, moleculele unui gaz la echilibru:
- sunt considerate a fi la aceeasi temperatura, dar pot avea diferite energii;
- toate au aceeasi viteza;
- toate se deplaseaza īn aceeasi directie;
- sunt considerate a fi la aceeasi temperatura, dar pot avea viteze diferite;
FINAL TEST AT LABORATORY
Study of the diffusion in gaseous state and molecular speeds
Do not use this paper to give answers!
Please decide which of the following statements are true.- At the ends of the tube following equilibrium reactions occurs:
- H+ + HO- \=\ H2O
- NH3 + H2O \=\ NH4+ + HO-
- HCl + H2O \=\ Cl- + H3O+
- NH3 + HCl \=\ NH4Cl
- We may say the followings:
- the kinetic energy of a molecule is affected by temperature and pressure;
- the molecules have speeds only in gaseous and liquid states;
- the molecules have energy only in gaseous state;
- diffusion process appears in all gaseous, liquid and solid states;
- The chronometer is used in the experiment for:
- measuring of the diffusion time;
- extracting the information necessary to calculate the diffusion coefficients;
- extracting the information necessary to calculate the speeds ratio;
- to keep us busy;
- The time to the formation of the ring in the experiment is dependent on:
- the speed of diffusion of each involved species;
- the real speeds and not the virtual speeds of each involved species;
- the width of the tube and not of the length of the tube;
- the mode energy or mode speed of each involved species;
- The fog observed during the experiment is due to:
- formation of ammonium chloride;
- unproper illumination in the laboratory or our breathing;
- presence of the ammonia;
- presence of the chlorine;
TEST DE FINAL DE LABORATOR
Studiul difuziei in stare gazoasa si a vitezelor moleculare
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- La capetele tubului urmatoarele reactii de echilibru apar:
- H+ + HO- \=\ H2O
- NH3 + H2O \ = \ NH4+ + HO-
- HCl + H2O \=\ Cl- + H3O+
- NH3 + HCl \=\ NH4Cl
- Va rugam sa decida cu adevarat / fals pentru urmatoarele afirmatii:
- energia cinetica a unei molecule este afectata de temperatura si presiune;
- moleculele au viteze numai īn stare gazoasa si lichida;
- moleculele au energie numai īn stare gazoasa;
- proces de difuzie apare īn toate starile gazoasa, lichida si solida;
- moleculele au energie numai īn stare gazoasa si lichida;
- Cronometrul este utilizat īn experimentul pentru:
- masurarea timpului de difuzie;
- extragerea informatiilor necesare pentru a calcula coeficientii de difuzie;
- extragerea informatiilor necesare pentru calcularea raportului vitezelor;
- sa ne tina ocupati;
- Timpul pentru formarea inelului īn experimentul este dependenta de:
- viteza de difuzie a fiecarei specii implicate;
- vitezele reale si nu vitezele virtuale ale fiecarei specii implicate;
- latimea tubului si nu lungimea tubului;
- viteza la moda sau energia la moda a fiecarei specii implicate;
- Ceata observata īn timpul experimentului se datoreaza:
- formarea clorurii de amoniu;
- iluminarii necorespunzatoare īn laborator sau respiratie noastre;
- prezentei amoniacului;
- prezentei clorului;
- iluminarii necorespunzatoare īn laborator si respiratiei noastre;
FINAL TEST AT LABORATORY
Obtaining of the oxygen: study of the gases laws
Do not use this paper to give answers!
Please decide which of the following statements are true.- The values taken from the experiment conducted in the laboratory indicated that:
- we do not possess enough information to decide what gas was released from the reaction;
- the ideal model of a gas approximated the worst the behavior of the released gas;
- the ideal model of a gas approximated the best the behavior of the released gas;
- ozone were released as result of the decomposition;
- In the laboratory were studied:
- the obtaining of the oxygen, by using the reaction KClO3 (+MnO2, heat) -> KCl + O2;
- increasing of the pressure of a gas when was heated;
- decomposition of the potasium chloride to potasium chlorate when oxygen is released;
- the producing of some gas as result of a lost of the mass of a solid;
- Based on our experience after conducting the experiment, we may say that the oxygen can be obtained from:
- H2O + O2 -> H2O2;
- K2Cr2O7 -> K2CrO4 + Cr2O3 + O2;
- Ag + O2 -> Ag2O;
- KMnO4 -> K2MnO4 + MnO2 + O2;
- For gaseous state:
- the pressure depends on the model which are used to approximate it;
- the pressure is much higher than in liquid state;
- the pressure is subject to change when a chemical reaction occurs;
- the pressure is exactly the same as in liquid state;
- A state equation for a real gas is:
- a relation which is always true, independent of the values of the state parameters;
- a relation which takes into account certain deviations from the ideal model;
- usable in the laboratory, but is not to be used somewhere else;
- a relation obtained after conducting of the experiment;
TEST DE FINAL DE LABORATOR
Obtinerea oxigenului: studiul legilor gazelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Valorile luate din experimentul efectuat īn laborator au indicat ca:
- nu avem suficiente informatii pentru a decide ce gaz a fost eliberat din reactie;
- modelul ideal al unui gaz aproximeaza cel mai rau comportamentul gazului eliberat;
- modelul ideal al unui gaz aproximeaza cel mai bine comportamentul gazului eliberat;
- ozonul au fost eliberat ca urmare a descompunerii;
- cu cat mai simplu este modelul folosit pentru a aproxima comportamentul, cu atat este mai bun este agrementul;
- Īn laborator s-au studiat:
- obtinerea de oxigen, folosind reactia KClO3(+ MnO2, caldura) -> KCl + O2;
- cresterea presiunii unui gaz cānd s-a īncalzit;
- descompunerea clorurii de potasiu la cloratul de potasiu cānd oxigenul este eliberat;
- producerea unor gaze ca urmare a unei pierderi de masa a unui solid;
- Pe baza experientei noastre dupa efectuarea experimentului, putem spune ca oxigenul poate fi obtinut din:
- H2O + O2 -> H2O2;
- K2Cr2O7 -> K2CrO4 + Cr2O3 + O2;
- Ag + O2 -> Ag2O;
- KMnO4 -> K2MnO4 + MnO2 + O2;
- K2CrO4 + Cr2O3 + O2 -> K2Cr2O7;
- Pentru stare gazoasa:
- presiunea depinde de modelul care este utilizat pentru o aproxima;
- presiunea este mult mai mare decāt īn stare lichida;
- presiunea se pot modifica atunci cānd apare o reactie chimica;
- presiunea este exact la fel ca si īn stare lichida;
- O ecuatie de stare pentru un gaz real este:
- o relatie care este īntotdeauna adevarata, independent de valorile parametrilor de stare;
- o relatie care sa tina cont de anumite abateri de la modelul ideal;
- utilizabila īn laborator, dar nu este de a fi utilizata īn alta parte;
- o relatie obtinut dupa efectuarea experimentului;
- o relatie īntre un anumit numar de parametri de stare;
FINAL TEST AT LABORATORY
Obtaining of the oxygen: study of the gases laws
Do not use this paper to give answers!
Please decide which of the following statements are true.- In the laboratory were studied:
- the obtaining of the oxygen, by using the reaction KClO3 (+MnO2, heat) -> KCl + O3;
- the obtaining of the oxygen, by using the reaction KClO3 (+MnO2, heat) -> KCl + O2;
- decomposition of the potasium chlorate to potasium chloride when ozone is released;
- decomposition of the potasium chloride to potasium chlorate when oxygen is released;
- A state equation for a real gas is:
- a relation derived to approximate the relation between state parameters;
- usable in the laboratory, but is not to be used somewhere else;
- a relation between an unlimited number of state parameters;
- a relation which is always true, independent of the values of the state parameters;
- The values taken from the experiment conducted in the laboratory indicated that:
- the ideal model of a gas approximated the worst the behavior of the released gas;
- the ideal model of a gas approximated the best the behavior of the released gas;
- we possess enough information to decide what gas was released from the reaction;
- ozone were released as result of the decomposition;
- Based on our experience after conducting the experiment, we may say that the oxygen can be obtained from:
- opening a bubble water bottle;
- Ag + O2 -> Ag2O;
- KNO3 -> KNO2 + O2;
- K2Cr2O7 -> K2CrO4 + Cr2O3 + O2;
- For gaseous state:
- it exists an equation for all, p · V = n · R · T;
- the pressure is approximately the same as in liquid state;
- the pressure is subject to change when a chemical reaction occurs;
- the pressure is much higher than in liquid state;
TEST DE FINAL DE LABORATOR
Obtinerea oxigenului: studiul legilor gazelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Īn laborator s-au studiat:
- obtinerea de oxigen, folosind reactia KClO3(+ MnO2, caldura) -> KCl + O3;
- obtinerea de oxigen, folosind reactia KClO3(+ MnO2, caldura) -> KCl + O2;
- descompunerea cloratului de potasiu la clorura de potasiu cānd ozonul este eliberat;
- descompunerea clorurii de potasiu la cloratul de potasiu cānd oxigenul este eliberat;
- cresterea temperaturii unei mase solide cānd s-a īncalzit;
- O ecuatie de stare pentru un gaz real este:
- o relatie derivata pentru a aproxima relatia dintre parametrii de stare;
- utilizabila īn laborator, dar nu este de a fi utilizata īn alta parte;
- o relatie īntre un numar nelimitat de parametri de stare;
- o relatie care este īntotdeauna adevarata, independent de valorile parametrilor de stare;
- Valorile luate din experimentul efectuat īn laborator au indicat ca:
- modelul ideal al unui gaz aproximeaza cel mai rau comportamentul gazului eliberat;
- modelul ideal al unui gaz aproximeaza cel mai bine comportamentul gazului eliberat;
- avem suficiente informatii pentru a decide ce gaz a fost eliberat din reactie;
- ozonul au fost eliberat ca urmare a descompunerii;
- Pe baza experientei noastre dupa efectuarea experimentului, putem spune ca oxigenul poate fi obtinut din:
- deschiderea unei sticle de apa cu bule;
- Ag + O2 -> Ag2O;
- KNO3 -> KNO2 + O2;
- K2Cr2O7 -> K2CrO4 + Cr2O3 + O2;
- H2O2 -> H2O + O2;
- Pentru stare gazoasa:
- ca exista o ecuatie utilizabila mereu, p · V = n · R · T;
- presiunea este aproximativ aceeasi ca si īn stare lichida;
- presiunea se pot modifica atunci cānd apare o reactie chimica;
- presiunea este mult mai mare decāt īn stare lichida;
FINAL TEST AT LABORATORY
Obtaining of the oxygen: study of the gases laws
Do not use this paper to give answers!
Please decide which of the following statements are true.- The values taken from the experiment conducted in the laboratory indicated that:
- ozone were released as result of the decomposition;
- the ideal model of a gas approximated the best the behavior of the released gas;
- air were released as result of the decomposition;
- we do not possess enough information to decide what gas was released from the reaction;
- For gaseous state:
- the pressure is unchanged when a chemical reaction occurs;
- the pressure is much higher than in liquid state;
- the pressure is subject to change when a chemical reaction occurs;
- the pressure depends on the model which are used to approximate it;
- A state equation for a real gas is:
- a relation between an unlimited number of state parameters;
- usable in the laboratory, but is not to be used somewhere else;
- a relation obtained after conducting of the experiment;
- a relation derived to approximate the relation between state parameters;
- In the laboratory were studied:
- the lost of the mass of a solid as result of producing of some gas;
- the producing of some gas as result of a lost of the mass of a solid;
- decomposition of the potasium chlorate to potasium chloride when oxygen is released;
- the obtaining of the oxygen, by using the reaction KClO3 (+MnO2, heat) -> KCl + O3;
- Based on our experience after conducting the experiment, we may say that the oxygen can be obtained from:
- Ag + O2 -> Ag2O;
- KNO2 + O2 -> KNO3;
- distillation of the liquid air;
- K2CrO4 + Cr2O3 + O2 -> K2Cr2O7;
TEST DE FINAL DE LABORATOR
Obtinerea oxigenului: studiul legilor gazelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Valorile luate din experimentul efectuat īn laborator au indicat ca:
- ozonul au fost eliberat ca urmare a descompunerii;
- modelul ideal al unui gaz aproximeaza cel mai bine comportamentul gazului eliberat;
- aer a fost eliberat ca urmare a descompunerii;
- nu avem suficiente informatii pentru a decide ce gaz a fost eliberat din reactie;
- Pentru stare gazoasa:
- presiunea este neschimbata cānd apare o reactie chimica;
- presiunea este mult mai mare decāt īn stare lichida;
- presiunea se pot modifica atunci cānd apare o reactie chimica;
- presiunea depinde de modelul care este utilizat pentru o aproxima;
- O ecuatie de stare pentru un gaz real este:
- o relatie īntre un numar nelimitat de parametri de stare;
- utilizabila īn laborator, dar nu este de a fi utilizata īn alta parte;
- o relatie obtinut dupa efectuarea experimentului;
- o relatie derivata pentru a aproxima relatia dintre parametrii de stare;
- o relatie care sa tina cont de anumite abateri de la modelul ideal;
- Īn laborator s-au studiat:
- pierdut din masa de solid ca urmare a producerii unor gaze;
- producerea unor gaze ca urmare a unei pierderi de masa a unui solid;
- descompunerea cloratului de potasiu la clorura de potasiu cānd oxigenul este eliberat;
- obtinerea de oxigen, folosind reactia KClO3(+ MnO2, caldura) -> KCl + O3;
- Pe baza experientei noastre dupa efectuarea experimentului, putem spune ca oxigenul poate fi obtinut din:
- Ag + O2 -> Ag2O;
- KNO2 + O2 -> KNO3;
- distilarea aerului lichid;
- K2CrO4 + Cr2O3 + O2 -> K2Cr2O7;
- K2Cr2O7 -> K2CrO4 + Cr2O3 + O2;
FINAL TEST AT LABORATORY
Obtaining of the oxygen: study of the gases laws
Do not use this paper to give answers!
Please decide which of the following statements are true.- For gaseous state:
- the pressure is approximately the same as in liquid state;
- the pressure is unchanged when a chemical reaction occurs;
- the pressure is subject to change when a chemical reaction occurs;
- the pressure is much lower than in liquid state;
- In the laboratory were studied:
- the producing of some gas as result of a lost of the mass of a solid;
- the obtaining of the oxygen, by using the reaction KClO3 (+MnO2, heat) -> KCl + O3;
- increasing of the temperature of a solid mass when was heated;
- decomposition of the potasium chlorate to potasium chloride when oxygen is released;
- The values taken from the experiment conducted in the laboratory indicated that:
- the ideal model of a gas approximated the worst the behavior of the released gas;
- we possess enough information to decide what gas was released from the reaction;
- oxigen were released as result of the decomposition;
- as more simple the model is used to approximate the behavior, as best agreement is obtained;
- A state equation for a real gas is:
- a relation between an certain number of state parameters;
- a relation which may involve some constants dependent of gas composition;
- a relation obtained after conducting of the experiment;
- a relation which is always true, independent of the values of the state parameters;
- Based on our experience after conducting the experiment, we may say that the oxygen can be obtained from:
- KCl + O2 -> KClO3;
- H2O2 -> H2O + O2;
- KMnO4 -> K2MnO4 + MnO2 + O2;
- KNO2 + O2 -> KNO3;
TEST DE FINAL DE LABORATOR
Obtinerea oxigenului: studiul legilor gazelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Pentru stare gazoasa:
- presiunea este aproximativ aceeasi ca si īn stare lichida;
- presiunea este neschimbata cānd apare o reactie chimica;
- presiunea se pot modifica atunci cānd apare o reactie chimica;
- presiunea este mult mai mica decāt īn stare lichida;
- Īn laborator s-au studiat:
- producerea unor gaze ca urmare a unei pierderi de masa a unui solid;
- obtinerea de oxigen, folosind reactia KClO3(+ MnO2, caldura) -> KCl + O3;
- cresterea temperaturii unei mase solide cānd s-a īncalzit;
- descompunerea cloratului de potasiu la clorura de potasiu cānd oxigenul este eliberat;
- Valorile luate din experimentul efectuat īn laborator au indicat ca:
- modelul ideal al unui gaz aproximeaza cel mai rau comportamentul gazului eliberat;
- avem suficiente informatii pentru a decide ce gaz a fost eliberat din reactie;
- oxigenul au fost eliberat ca urmare a descompunerii;
- cu cat mai simplu este modelul folosit pentru a aproxima comportamentul, cu atat este mai bun este agrementul;
- ozonul au fost eliberat ca urmare a descompunerii;
- O ecuatie de stare pentru un gaz real este:
- o relatie īntre un anumit numar de parametri de stare;
- o relatie care poate implica unele constante dependente de compozitia gazului;
- o relatie obtinut dupa efectuarea experimentului;
- o relatie care este īntotdeauna adevarata, independent de valorile parametrilor de stare;
- o relatie derivata pentru a aproxima relatia dintre parametrii de stare;
- Pe baza experientei noastre dupa efectuarea experimentului, putem spune ca oxigenul poate fi obtinut din:
- KCl + O2 -> KClO3;
- H2O2 -> H2O + O2;
- KMnO4 -> K2MnO4 + MnO2 + O2;
- KNO2 + O2 -> KNO3;
- deschiderea unei sticle de apa cu bule;
FINAL TEST AT LABORATORY
Obtaining of the oxygen: study of the gases laws
Do not use this paper to give answers!
Please decide which of the following statements are true.- The values taken from the experiment conducted in the laboratory indicated that:
- as more simple the model is used to approximate the behavior, as best agreement is obtained;
- ozone were released as result of the decomposition;
- we do not possess enough information to decide what gas was released from the reaction;
- air were released as result of the decomposition;
- In the laboratory were studied:
- the producing of some gas as result of a lost of the mass of a solid;
- the obtaining of the oxygen, by using the reaction KClO3 (+MnO2, heat) -> KCl + O2;
- increasing of the temperature of a solid mass when was heated;
- increasing of the pressure of a gas when was heated;
- A state equation for a real gas is:
- a relation between an unlimited number of state parameters;
- a relation which may involve some constants dependent of gas composition;
- a relation between an certain number of state parameters;
- usable in the laboratory, but is not to be used somewhere else;
- Based on our experience after conducting the experiment, we may say that the oxygen can be obtained from:
- KCl + O2 -> KClO3;
- K2Cr2O7 -> K2CrO4 + Cr2O3 + O2;
- KNO2 + O2 -> KNO3;
- K2MnO4 + MnO2 + O2 -> KMnO4;
- For gaseous state:
- it exists an equation for all, p · V = n · R · T;
- the pressure is much higher than in liquid state;
- the pressure is approximately the same as in liquid state;
- the pressure is much lower than in liquid state;
TEST DE FINAL DE LABORATOR
Obtinerea oxigenului: studiul legilor gazelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Valorile luate din experimentul efectuat īn laborator au indicat ca:
- cu cat mai simplu este modelul folosit pentru a aproxima comportamentul, cu atat este mai bun este agrementul;
- ozonul au fost eliberat ca urmare a descompunerii;
- nu avem suficiente informatii pentru a decide ce gaz a fost eliberat din reactie;
- aer a fost eliberat ca urmare a descompunerii;
- modelul ideal al unui gaz aproximeaza cel mai rau comportamentul gazului eliberat;
- Īn laborator s-au studiat:
- producerea unor gaze ca urmare a unei pierderi de masa a unui solid;
- obtinerea de oxigen, folosind reactia KClO3(+ MnO2, caldura) -> KCl + O2;
- cresterea temperaturii unei mase solide cānd s-a īncalzit;
- cresterea presiunii unui gaz cānd s-a īncalzit;
- descompunerea cloratului de potasiu la clorura de potasiu cānd oxigenul este eliberat;
- O ecuatie de stare pentru un gaz real este:
- o relatie īntre un numar nelimitat de parametri de stare;
- o relatie care poate implica unele constante dependente de compozitia gazului;
- o relatie īntre un anumit numar de parametri de stare;
- utilizabila īn laborator, dar nu este de a fi utilizata īn alta parte;
- Pe baza experientei noastre dupa efectuarea experimentului, putem spune ca oxigenul poate fi obtinut din:
- KCl + O2 -> KClO3;
- K2Cr2O7 -> K2CrO4 + Cr2O3 + O2;
- KNO2 + O2 -> KNO3;
- K2MnO4 + MnO2 + O2 -> KMnO4;
- Ag2O -> Ag + O2;
- Pentru stare gazoasa:
- ca exista o ecuatie utilizabila mereu, p · V = n · R · T;
- presiunea este mult mai mare decāt īn stare lichida;
- presiunea este aproximativ aceeasi ca si īn stare lichida;
- presiunea este mult mai mica decāt īn stare lichida;
- presiunea este neschimbata cānd apare o reactie chimica;
FINAL TEST AT LABORATORY
Qualitative analysis of metals and alloys
Do not use this paper to give answers!
Please decide which of the following statements are true.- Why moisten the paper with solution of sodium nitrate?
- to be cut easily with scissors;
- to work as an electrolyte and to allow passing of the electrical current through moistened paper;
- to accomodate ourselves to use chemicals;
- to provide cations for analysis;
- When aluminum is identified:
- the presence of other ions may produce a false positive outcome;
- using of ammonium hidroxide is enough in order to have a clear guess about the presence of aluminum;
- the presence of other ions may produce a true negative outcome;
- is identified as Al3+ cation;
- The paper requires before analysis of the sample:
- to be weighted;
- to be moistened with an electrolyte;
- to be cut in small pieces;
- to be burned;
- The electric charges after passing the metals into solution may be:
- Fe2+; Ni3+; Cu1+; Zn3+; Co3+; Cr2+
- Fe2+; Pb2+; Sn4+; Zn2+; Co5+; Cr6+
- Fe2+; Ni1+; Cu1+; Zn3+; Co2+; Cr6+
- Fe2+; Co2+; Ni2+; Cu2+; Zn2+; Al3+
- When lead is identified:
- precautions should be made for toxic wastes disposal;
- a blue complex appears;
- a heat release is observed;
- a yellow complex appears;
TEST DE FINAL DE LABORATOR
Analiza calitativa a metalelor si aliajelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- De ce umezim hārtia cu solutie de azotat de sodiu?
- sa fie taiat cu usurinta cu foarfeca;
- pentru a lucra ca un electrolit si pentru a permite trecerea de curent electric prin hārtia umezita;
- sa ne acomodam in a utiliza substante chimice;
- pentru furniza cationi pentru analiza;
- pentru ca hartia sa actioneze ca izolator;
- Cānd aluminiu este identificat:
- prezenta altor ioni poate produce un rezultat fals pozitiv;
- folosirea hidroxidului de amoniu este suficient pentru a avea indicii clare cu privire la prezenta aluminiului;
- prezenta altor ioni poate produce un rezultat adevarat negativ;
- este identificat ca cationul Al3+;
- prezenta altor ioni poate produce un rezultat adevarat pozitiv;
- Hartia necesita ca īnainte de analiza probei:
- sa fie cantarita;
- sa fie umezita cu un electrolit;
- sa fie taiata īn bucati mici;
- sa fie arsa;
- Sarcinile electrice ce apar la trecerea metalelor īn solutie pot fi:
- Fe2+; Ni3+; Cu1+; Zn3+; Co3+; Cr2+
- Fe2+; Pb2+; Sn4+; Zn2+; Co5+; Cr6+
- Fe2+; Ni1+; Cu1+; Zn3+; Co2+; Cr6+
- Fe2+; Co2+; Ni2+; Cu2+; Zn2+; Al3+
- Fe3+; Ni2+; Cu2+; Zn2+; Co2+; Cr3+
- Cānd plumbul este identificat:
- ar trebui sa fie luate masuri de precautie pentru deseurile toxice eliminate;
- apare un complex albastru;
- se observa o eliberare de caldura;
- apare un complex galben;
- apare un complex violet;
FINAL TEST AT LABORATORY
Qualitative analysis of metals and alloys
Do not use this paper to give answers!
Please decide which of the following statements are true.- The electric charges after passing the metals into solution may be:
- Fe2+; Pb2+; Sn4+; Zn2+; Co5+; Cr6+
- Fe2+; Ni4+; Cu1+; Zn2+; Co5+; Cr6+
- Fe2+; Co2+; Ni2+; Cu2+; Zn2+; Al3+
- Fe2+; Ni3+; Cu1+; Zn3+; Co3+; Cr2+
- Why moisten the paper with solution of sodium nitrate?
- to work as an electrolyte and to allow passing of the electrical current through moistened paper;
- to be cut easily with scissors;
- for stopping after a while the chemical reaction that takes place;
- to provide cations for analysis;
- When lead is identified:
- a yellow complex appears;
- a heat release is observed;
- precautions should be made for toxic wastes disposal;
- a violet complex appears;
- The paper requires before analysis of the sample:
- to be dry;
- to be burned;
- to be acidified;
- to be cut in small pieces;
- This method of analysis of metals and alloys is:
- useful for pure metals, not so useful for alloys;
- too ancient to be used today in the laboratory;
- useful for both metals and alloys;
- useful for alloys, not so useful for metals;
TEST DE FINAL DE LABORATOR
Analiza calitativa a metalelor si aliajelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Sarcinile electrice ce apar la trecerea metalelor īn solutie pot fi:
- Fe2+; Pb2+; Sn4+; Zn2+; Co5+; Cr6+
- Fe2+; Ni4+; Cu1+; Zn2+; Co5+; Cr6+
- Fe2+; Co2+; Ni2+; Cu2+; Zn2+; Al3+
- Fe2+; Ni3+; Cu1+; Zn3+; Co3+; Cr2+
- Fe2+; Ni1+; Cu1+; Zn3+; Co2+; Cr6+
- De ce umezim hārtia cu solutie de azotat de sodiu?
- pentru a lucra ca un electrolit si pentru a permite trecerea de curent electric prin hārtia umezita;
- sa fie taiat cu usurinta cu foarfeca;
- pentru oprirea dupa un timp reactiei chimice care are loc;
- pentru furniza cationi pentru analiza;
- pentru ca hartia sa actioneze ca izolator;
- Cānd plumbul este identificat:
- apare un complex galben;
- se observa o eliberare de caldura;
- ar trebui sa fie luate masuri de precautie pentru deseurile toxice eliminate;
- apare un complex violet;
- Hartia necesita ca īnainte de analiza probei:
- sa fie uscata;
- sa fie arsa;
- sa fie acidulata;
- sa fie taiata īn bucati mici;
- Aceasta metoda de analiza de metale si aliaje este:
- utila pentru metale pure, nu atāt de utila pentru aliaje;
- prea veche pentru a fi utilizata īn prezent īn laborator;
- utila atāt pentru metale si aliaje;
- utila pentru aliaje, nu atāt de utila pentru metale;
FINAL TEST AT LABORATORY
Qualitative analysis of metals and alloys
Do not use this paper to give answers!
Please decide which of the following statements are true.- The paper requires before analysis of the sample:
- to be tested;
- to be acidified;
- to be burned;
- to be weighted;
- The electric charges after passing the metals into solution may be:
- Fe2+; Ni2+; Cu2+; Zn2+; Co2+; Cr3+
- Fe2+; Ni4+; Cu1+; Zn2+; Co5+; Cr6+
- Fe3+; Ni2+; Cu2+; Zn2+; Co2+; Cr3+
- Fe2+; Pb2+; Sn4+; Zn2+; Co5+; Cr6+
- This method of analysis of metals and alloys is:
- a quantitative method of analysis;
- a destructive method of analysis;
- too ancient to be used today in the laboratory;
- useful for pure metals, not so useful for alloys;
- When aluminum is identified:
- only one identification reaction is possible;
- the presence of other ions may produce a true negative outcome;
- the presence of other ions may produce a false positive outcome;
- is identified as Al2+ cation;
- Why moisten the paper with solution of sodium nitrate?
- for the paper to work as isolator;
- to provide cations for analysis;
- to have something to do in the laboratory;
- to be cut easily with scissors;
TEST DE FINAL DE LABORATOR
Analiza calitativa a metalelor si aliajelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Hartia necesita ca īnainte de analiza probei:
- sa fie testata;
- sa fie acidulata;
- sa fie arsa;
- sa fie cantarita;
- Sarcinile electrice ce apar la trecerea metalelor īn solutie pot fi:
- Fe2+; Ni2+; Cu2+; Zn2+; Co2+; Cr3+
- Fe2+; Ni4+; Cu1+; Zn2+; Co5+; Cr6+
- Fe3+; Ni2+; Cu2+; Zn2+; Co2+; Cr3+
- Fe2+; Pb2+; Sn4+; Zn2+; Co5+; Cr6+
- Aceasta metoda de analiza de metale si aliaje este:
- o metoda cantitativa de analiza;
- o metoda distructiva de analiza;
- prea veche pentru a fi utilizata īn prezent īn laborator;
- utila pentru metale pure, nu atāt de utila pentru aliaje;
- nu este utila nici pentru metale nici pentru aliaje;
- Cānd aluminiu este identificat:
- doar o reactie de identificare este posibila;
- prezenta altor ioni poate produce un rezultat adevarat negativ;
- prezenta altor ioni poate produce un rezultat fals pozitiv;
- este identificat ca cationul Al2+;
- este identificat ca cationul Al1+;
- De ce umezim hārtia cu solutie de azotat de sodiu?
- pentru ca hartia sa actioneze ca izolator;
- pentru furniza cationi pentru analiza;
- pentru a avea ceva de a face īn laborator;
- sa fie taiat cu usurinta cu foarfeca;
- pentru a lucra ca un electrolit si pentru a permite trecerea de curent electric prin hārtia umezita;
FINAL TEST AT LABORATORY
Qualitative analysis of metals and alloys
Do not use this paper to give answers!
Please decide which of the following statements are true.- Why moisten the paper with solution of sodium nitrate?
- for stopping after a while the chemical reaction that takes place;
- to accomodate ourselves to use chemicals;
- to provide cations for analysis;
- for the paper to work as isolator;
- When the electrical circuit is closed:
- surface of the sample is fastly covered by a protecting shield of electrons;
- cations from the solution are passed into sample as metals;
- electric current avoids the sample and the paper;
- elements from the metals are passed into solution as anions;
- When aluminum is identified:
- the presence of other ions may produce a false positive outcome;
- using of alizarin along with ammonium hidroxide provide a red colored complex;
- only one identification reaction is possible;
- is identified as Al2+ cation;
- When lead is identified:
- a red-brown complex appears;
- dangerous substances are used;
- a violet complex appears;
- a blue complex appears;
- This method of analysis of metals and alloys is:
- a destructive method of analysis;
- a nondestructive method of analysis;
- not useful for both metals and alloys;
- useful for both metals and alloys;
TEST DE FINAL DE LABORATOR
Analiza calitativa a metalelor si aliajelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- De ce umezim hārtia cu solutie de azotat de sodiu?
- pentru oprirea dupa un timp reactiei chimice care are loc;
- sa ne acomodam in a utiliza substante chimice;
- pentru furniza cationi pentru analiza;
- pentru ca hartia sa actioneze ca izolator;
- Cānd circuitul electric este īnchis:
- suprafata probei este cu rapiditate acoperita de un strat protector de electroni;
- cationii din solutie sunt trecuti īn proba ca metale;
- curent electric evita proba si hārtia;
- elemente din metalele sunt trecute īn solutie sub forma de anioni;
- elementele din metalele sunt trecute īn solutie sub forma de cationi;
- Cānd aluminiu este identificat:
- prezenta altor ioni poate produce un rezultat fals pozitiv;
- folosirea alizarinei, īmpreuna cu hidroxidul de amoniu ofera un complex colorat rosu;
- doar o reactie de identificare este posibila;
- este identificat ca cationul Al2+;
- este identificat ca cationul Al3+;
- Cānd plumbul este identificat:
- apare un complex rosu-brun;
- sunt utilizate substante periculoase;
- apare un complex violet;
- apare un complex albastru;
- Aceasta metoda de analiza de metale si aliaje este:
- o metoda distructiva de analiza;
- o metoda nedistructiva de analiza;
- nu este utila nici pentru metale nici pentru aliaje;
- utila atāt pentru metale si aliaje;
- prea veche pentru a fi utilizata īn prezent īn laborator;
FINAL TEST AT LABORATORY
Qualitative analysis of metals and alloys
Do not use this paper to give answers!
Please decide which of the following statements are true.- Why moisten the paper with solution of sodium nitrate?
- for stopping after a while the chemical reaction that takes place;
- to work as an electrolyte and to allow passing of the electrical current through moistened paper;
- to accomodate ourselves to use chemicals;
- to be cut easily with scissors;
- The paper requires before analysis of the sample:
- to measure its surface;
- to be dry;
- to be acidified;
- to be moistened with an electrolyte;
- When the electrical circuit is closed:
- electric current avoids the sample and the paper;
- elements from the metals are passed into solution as anions;
- elements from the solution are passed into sample as metals;
- water dissociation is inhibited;
- When lead is identified:
- dangerous substances are used;
- interference of other ions may affect the outcome;
- the reactions used clearly indicates its presence;
- a violet complex appears;
- This method of analysis of metals and alloys is:
- useful for both metals and alloys;
- too ancient to be used today in the laboratory;
- a destructive method of analysis;
- useful for pure metals, not so useful for alloys;
TEST DE FINAL DE LABORATOR
Analiza calitativa a metalelor si aliajelor
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- De ce umezim hārtia cu solutie de azotat de sodiu?
- pentru oprirea dupa un timp reactiei chimice care are loc;
- pentru a lucra ca un electrolit si pentru a permite trecerea de curent electric prin hārtia umezita;
- sa ne acomodam in a utiliza substante chimice;
- sa fie taiat cu usurinta cu foarfeca;
- Hartia necesita ca īnainte de analiza probei:
- sa i se masoare suprafata;
- sa fie uscata;
- sa fie acidulata;
- sa fie umezita cu un electrolit;
- sa fie taiata īn bucati mici;
- Cānd circuitul electric este īnchis:
- curent electric evita proba si hārtia;
- elemente din metalele sunt trecute īn solutie sub forma de anioni;
- elemente din solutie sunt trecute īn proba ca metale;
- disocierea apei este inhibata;
- suprafata probei este cu rapiditate acoperita de un strat protector de electroni;
- Cānd plumbul este identificat:
- sunt utilizate substante periculoase;
- interferenta altor ioni poate afecta rezultatul;
- reactiile utilizate īn mod clar ii indica prezenta;
- apare un complex violet;
- apare un complex albastru;
- Aceasta metoda de analiza de metale si aliaje este:
- utila atāt pentru metale si aliaje;
- prea veche pentru a fi utilizata īn prezent īn laborator;
- o metoda distructiva de analiza;
- utila pentru metale pure, nu atāt de utila pentru aliaje;
- o metoda nedistructiva de analiza;
FINAL TEST AT LABORATORY
Study of chemical reactions
Do not use this paper to give answers!
Please decide which of the following statements are true.- A redox process:
- is considered to be the following one: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- occurs only when we mix wrong substances in the laboratory;
- is considered to be the following one: H2SO4 + NaOH -> Na2SO4 + H2O
- involves changing of the aggregation states of some participants to the reaction;
- Reactions between acids and bases:
- have as a consequence the dissolution of a salt;
- are always fast, taking place almost instantaneously;
- are rarely useful, and even rarely used;
- are all exothermic, being therefore dangerous outside of the laboratory;
- Titration as a laboratory operation involves:
- a volume measurement;
- a mass measurement;
- a standard or referential reactive;
- a natrium hydroxide solution;
- The indicator should be added:
- in large quantities, according to the principle 'only size matters';
- only at the suggestion of the supervisor;
- only in special cases, when the burette is graded from its bottom to its top;
- to be able to use the chemical reaction for the calculation of corresponding quantities of reactives;
- The following chemical reactions were used in the experiments:
- KMnO4 + H2SO4 -> K2SO4 + MnSO4 + H2O
- H2O + CO2 -> H2CO3
- (COOH)2 + NaOH -> (COONa)2 + H2O
- KMnO4 + NaOH -> Na2MnO4 + KOH
TEST DE FINAL DE LABORATOR
Studiul reactiilor chimice
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Un proces redox:
- este considerat a fi urmatorul: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- apare numai atunci cānd se amesteca substante gresit īn laborator;
- este considerat a fi urmatorul: H2SO4 + NaOH -> Na2SO4 + H2O
- implica schimbarea a starilor de agregare ale unor participanti la reactie;
- Reactiile īntre acizi si baze:
- au drept consecinta dizolvarea unei sari;
- sunt īntotdeauna rapide, avānd loc aproape instantaneu;
- sunt rareori utile, si chiar mai rar utilizate;
- sunt toate exoterme, fiind, prin urmare, īn afara laboratorului periculoase;
- au ca efect schimbarea culorii unei solutii;
- Titrarea ca o operatiune de laborator implica:
- masurarea volumului;
- masurarea masei;
- un standard sau reactiv de referinta;
- o solutie de hidroxid de sodiu;
- Trebuie adaugat indicatorul:
- īn cantitati mari, īn conformitate cu principiul "doar dimensiunea conteaza";
- numai la sugestia supraveghetorului;
- numai īn cazuri speciale, atunci cānd este biureta gradata de jos in sus;
- pentru a putea utiliza reactia chimica in calculul cantitatilor de reactivi corespunzatoare;
- Urmatoarele reactii chimice au fost folosite īn experimente:
- KMnO4 + H2SO4 -> K2SO4 + MnSO4 + H2O
- H2O + CO2 -> H2CO3
- (COOH)2 + NaOH -> (COONa)2 + H2O
- KMnO4 + NaOH -> Na2MnO4 + KOH
FINAL TEST AT LABORATORY
Study of chemical reactions
Do not use this paper to give answers!
Please decide which of the following statements are true.- In the calculations:
- are necessary to use our phones;
- are necessary to draw the tables in our notebooks after completing of the experiment;
- are necessary to use some formulas expressing in different ways the concentration;
- are necessary to take the results imediatly after these are available from others;
- A redox process:
- is always fast and safe;
- is considered to be the following one: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- is considered to be the following one: H2SO4 + NaOH -> Na2SO4 + H2O
- involves changing of the aggregation states of some participants to the reaction;
- Titration as a laboratory operation involves:
- a burette;
- a natrium hydroxide solution;
- a sulphuric acid solution;
- a volume measurement;
- When a chemical reaction is balanced, following should be considered:
- the principle of the conservation of the volume;
- all glassware should be clean before, after and during the experiment;
- the principle of the conservation of the number of atoms for each element;
- the principle of the conservation of the energy;
- The equivalence point is:
- the point in which a reactive should be added in the burette;
- something rarely encountered in chemistry;
- the point in which a reactive is fully consumed in the reaction;
- indicated when a color change is observed into the solution;
TEST DE FINAL DE LABORATOR
Studiul reactiilor chimice
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- In calcule:
- este necesar sa utilizam telefoanele;
- este necesar sa desenam tabelele in caiete dupa finalizarea experimentului;
- este necesar sa utilizam unele formule care exprima īn moduri diferite concentratia;
- este necesar sa luam rezultatele imediat ce acestea devin disponibile de la colegii nostrii;
- este necesar a se lua unele informatii de pe sticlele de reactivi;
- Un proces redox:
- este īntotdeauna rapid si sigur;
- este considerat a fi urmatorul: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- este considerat a fi urmatorul: H2SO4 + NaOH -> Na2SO4 + H2O
- implica schimbarea a starilor de agregare ale unor participanti la reactie;
- Titrarea ca o operatiune de laborator implica:
- o biureta;
- o solutie de hidroxid de sodiu;
- o solutie de acid sulfuric;
- masurarea volumului;
- Cānd o reactie chimica este echilibrat, ar trebui sa fie luate īn considerare urmatoarele:
- principiul conservarii volumului;
- toate sticlariile trebuie sa fie curat īnainte, dupa, si īn timpul experimentului;
- principiul conservarii numarul de atomi pentru fiecare element;
- principiul conservarii energiei;
- lichidul din biureta ar trebui sa fie la acelasi nivel, īnainte si dupa efectuarea experimentului;
- Punctul de echivalenta este:
- punctul īn care ar trebui sa fie adaugat un reactiv īn biureta;
- ceva rar īntālnit īn chimie;
- punctul īn care un reactiv este consumat complet īn reactie;
- indicat atunci cānd o schimbare de culoare se observa īn solutie;
- folosit pentru a echilibra ecuatia;
FINAL TEST AT LABORATORY
Study of chemical reactions
Do not use this paper to give answers!
Please decide which of the following statements are true.- The equivalence point is:
- something rarely encountered in chemistry;
- the point in which a reactive is fully consumed in the reaction;
- indicated when a color change is observed into the solution;
- used to balance the equation;
- A redox process:
- involves changing of the oxidation states of some participants to the reaction;
- is always fast and safe;
- involves changing of the aggregation states of some participants to the reaction;
- is considered to be the following one: H2SO4 + NaOH -> Na2SO4 + H2O
- Reactions between acids and bases:
- are rarely useful, and even rarely used;
- have as a consequence the dissolution of a salt;
- are always fast, taking place almost instantaneously;
- are all exothermic, being therefore dangerous outside of the laboratory;
- The density of the solutions depends on:
- provider;
- quantity;
- time elapsed since were prepared;
- concentration;
- Titration as a laboratory operation involves:
- a burette;
- a standard or referential reactive;
- an mixing of two ore more solutions;
- a sulphuric acid solution;
TEST DE FINAL DE LABORATOR
Studiul reactiilor chimice
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Punctul de echivalenta este:
- ceva rar īntālnit īn chimie;
- punctul īn care un reactiv este consumat complet īn reactie;
- indicat atunci cānd o schimbare de culoare se observa īn solutie;
- folosit pentru a echilibra ecuatia;
- Un proces redox:
- implica schimbarea a starilor de oxidare ale unor participanti la reactie;
- este īntotdeauna rapid si sigur;
- implica schimbarea a starilor de agregare ale unor participanti la reactie;
- este considerat a fi urmatorul: H2SO4 + NaOH -> Na2SO4 + H2O
- este considerat a fi urmatorul: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- Reactiile īntre acizi si baze:
- sunt rareori utile, si chiar mai rar utilizate;
- au drept consecinta dizolvarea unei sari;
- sunt īntotdeauna rapide, avānd loc aproape instantaneu;
- sunt toate exoterme, fiind, prin urmare, īn afara laboratorului periculoase;
- Densitatea solutiilor depinde de:
- furnizor;
- cantitate;
- timpul scurs de cand au fost pregatite;
- concentratie;
- Titrarea ca o operatiune de laborator implica:
- o biureta;
- un standard sau reactiv de referinta;
- amestecul a doua sau mai multe solutii;
- o solutie de acid sulfuric;
- o solutie de sare;
FINAL TEST AT LABORATORY
Study of chemical reactions
Do not use this paper to give answers!
Please decide which of the following statements are true.- The equivalence point is:
- indicated when a color change is observed into the solution;
- something rarely encountered in chemistry;
- the point in which a reactive is fully consumed in the reaction;
- the point in which a reactive should be added in the reaction flask;
- The indicator should be added:
- in small quantities, to avoid the errors in observations and in calculations;
- only in special cases, when the burette is graded from its bottom to its top;
- only at the suggestion of the supervisor;
- in large quantities, according to the principle 'only size matters';
- The density of the solutions depends on:
- quantity;
- provider;
- concentration;
- temperature;
- A redox process:
- involves changing of the oxidation states of some participants to the reaction;
- is considered to be the following one: (COOH)2 + NaOH -> (COONa)2 + H2O
- occurs only when we mix wrong substances in the laboratory;
- is considered to be the following one: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- Titration as a laboratory operation involves:
- a mass measurement;
- a sulphuric acid solution;
- a pH indicator that changes color depending on the pH of the solution;
- an mixing of two ore more solutions;
TEST DE FINAL DE LABORATOR
Studiul reactiilor chimice
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Punctul de echivalenta este:
- indicat atunci cānd o schimbare de culoare se observa īn solutie;
- ceva rar īntālnit īn chimie;
- punctul īn care un reactiv este consumat complet īn reactie;
- punctul īn care ar trebui sa fie adaugat un reactiv īn balonul de reactie;
- folosit pentru a echilibra ecuatia;
- Trebuie adaugat indicatorul:
- īn cantitati mici, pentru a evita erorile īn observatii si īn calculele;
- numai īn cazuri speciale, atunci cānd este biureta gradata de jos in sus;
- numai la sugestia supraveghetorului;
- īn cantitati mari, īn conformitate cu principiul "doar dimensiunea conteaza";
- pentru a oferi o schimbare de culoare la punctul de echivalenta;
- Densitatea solutiilor depinde de:
- cantitate;
- furnizor;
- concentratie;
- temperatura;
- presiune;
- Un proces redox:
- implica schimbarea a starilor de oxidare ale unor participanti la reactie;
- este considerat a fi urmatorul: (COOH)2 + NaOH -> (COONa)2 + H2O
- apare numai atunci cānd se amesteca substante gresit īn laborator;
- este considerat a fi urmatorul: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- Titrarea ca o operatiune de laborator implica:
- masurarea masei;
- o solutie de acid sulfuric;
- un indicator de pH care īsi schimba culoarea īn functie de pH-ul solutiei;
- amestecul a doua sau mai multe solutii;
FINAL TEST AT LABORATORY
Study of chemical reactions
Do not use this paper to give answers!
Please decide which of the following statements are true.- The indicator should be added:
- to indicate our safety limits when we dealt with chemicals;
- to be able to use the chemical reaction for the calculation of corresponding quantities of reactives;
- in small quantities, to avoid the errors in observations and in calculations;
- to provide a color change at equivalence point;
- When a chemical reaction is balanced, following should be considered:
- all glassware should be clean before, after and during the experiment;
- the liquid in the burette should be at the same level before and after conducting the experiment;
- the principle of the conservation of the energy;
- all glassware should be clean before and after conducting the experiment;
- Reactions between acids and bases:
- are rarely useful, and even rarely used;
- are all exothermic, being therefore dangerous outside of the laboratory;
- have as a consequence the dissolution of a salt;
- are always fast, taking place almost instantaneously;
- The density of the solutions depends on:
- pressure;
- time elapsed since were prepared;
- concentration;
- provider;
- A redox process:
- is considered to be the following one: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- occurs only when we mix wrong substances in the laboratory;
- involves changing of the oxidation states of some participants to the reaction;
- is considered to be the following one: (COOH)2 + NaOH -> (COONa)2 + H2O
TEST DE FINAL DE LABORATOR
Studiul reactiilor chimice
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Trebuie adaugat indicatorul:
- pentru a indica limitele noastre de siguranta, atunci cānd ne ocupam cu substante chimice;
- pentru a putea utiliza reactia chimica in calculul cantitatilor de reactivi corespunzatoare;
- īn cantitati mici, pentru a evita erorile īn observatii si īn calculele;
- pentru a oferi o schimbare de culoare la punctul de echivalenta;
- īn cantitati mari, īn conformitate cu principiul "doar dimensiunea conteaza";
- Cānd o reactie chimica este echilibrat, ar trebui sa fie luate īn considerare urmatoarele:
- toate sticlariile trebuie sa fie curat īnainte, dupa, si īn timpul experimentului;
- lichidul din biureta ar trebui sa fie la acelasi nivel, īnainte si dupa efectuarea experimentului;
- principiul conservarii energiei;
- toate sticlariile trebuie sa fie curat īnainte si dupa efectuarea experimentului;
- Reactiile īntre acizi si baze:
- sunt rareori utile, si chiar mai rar utilizate;
- sunt toate exoterme, fiind, prin urmare, īn afara laboratorului periculoase;
- au drept consecinta dizolvarea unei sari;
- sunt īntotdeauna rapide, avānd loc aproape instantaneu;
- au ca efect schimbarea culorii unei solutii;
- Densitatea solutiilor depinde de:
- presiune;
- timpul scurs de cand au fost pregatite;
- concentratie;
- furnizor;
- Un proces redox:
- este considerat a fi urmatorul: KMnO4 + (COOH)2 + H2SO4 -> K2SO4 + MnSO4 + CO2 + H2O
- apare numai atunci cānd se amesteca substante gresit īn laborator;
- implica schimbarea a starilor de oxidare ale unor participanti la reactie;
- este considerat a fi urmatorul: (COOH)2 + NaOH -> (COONa)2 + H2O
- este īntotdeauna rapid si sigur;
FINAL TEST AT LABORATORY
Water analysis
Do not use this paper to give answers!
Please decide which of the following statements are true.- Following reactions may tok place when we analyse a sample of water for partial alkalinity:
- HCl + HO- -> H2O + Cl-
- HCl + PO43+ -> HPO42+ + Cl+
- HCl + HO+ -> H2O + Cl+
- HCl + CO32+ -> HCO3+ + Cl+
- Following reactions may tok place when we analyse a sample of water for mineral acidity:
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + Zn2+ -> Zn(OH)2 + Na+
- NaOH + Cl+ -> NaCl + HO+
- NaOH + NO3+ -> NaNO3 + HO+
- EDTA is used:
- as reagent for determining the hardness of the water;
- for complexing of Na1+ and K1+ ions;
- for indication of the equilibrium point in the reaction;
- for safety precautions purposes;
- We may say the followings:
- water is a good polar solvent;
- purification of the water may include chemical processes;
- water is pure only when is taken from a good freshwater mountain stream;
- purification of the water may include physical processes;
- For a water sample following measures may be quantitatively expressed:
- total alkalinity;
- hardness;
- total acidity;
- mineral acidity;
TEST DE FINAL DE LABORATOR
Analiza apei
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru alcalinitate partiala:
- HCl + HO- -> H2O+Cl-
- HCl + PO43+ -> HPO42+ + Cl+
- HCl + HO+ -> H2O + Cl+
- HCl + CO32+ -> HCO3+ + Cl+
- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru aciditate minerala:
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + Zn2+ -> Zn(OH)2 + Na+
- NaOH + Cl+ -> NaCl + HO+
- NaOH + NO3+ -> NaNO3 + HO+
- EDTA este utilizat:
- ca reactiv pentru determinarea duritatii apei;
- pentru complexarea ionilor de Na1 +si K1 +;
- pentru indicarea punctului de echilibru īn reactie;
- ca masura de siguranta;
- Putem spune urmatoarele:
- apa este un solvent polar bun;
- purificarea apei poate include procese chimice;
- apa este pura doar atunci cānd este luata dintr-un bun izvor de munte de apa dulce;
- purificarea apei poate include procedee fizice;
- apa naturala poate contine materie organica si organisme vii;
- Pentru o proba de apa urmatoarele masuri pot fi exprimate cantitativ:
- alcalinitate totala;
- duritate;
- aciditate totala;
- aciditate minerala;
FINAL TEST AT LABORATORY
Water analysis
Do not use this paper to give answers!
Please decide which of the following statements are true.- We may say the followings:
- natural water may contain organic matter and living organisms;
- purification of the water may include physical processes;
- water is pure only when is taken from a good freshwater mountain stream;
- water is a good polar solvent;
- Following reactions may tok place when we analyse a sample of water for mineral acidity:
- NaOH + Cl- -> NaCl + HO-
- NaOH + SO42- -> Na2SO4 + HO-
- NaOH + Cl+ -> NaCl + HO+
- NaOH + NO3- -> NaNO3 + HO-
- Following reactions may tok place when we analyse a sample of water for total alkalinity:
- HCl + CO32+ -> H2CO3 + Cl+
- HCl + HO- -> H2O + Cl-
- HCl + PO43+ -> H2PO4+ + Cl+
- HCl + HO+ -> H2O + Cl+
- In the laboratory the water were:
- complexed by using EDTA titrimetric method;
- softened using the resin column;
- acidified for drinking purposes;
- hardened using the resin column;
- EDTA is used:
- for complexing of Ca2+ and Mg2+ ions;
- for complexing of Na1+ and K1+ ions;
- as reagent for determining the hardness of the water;
- for recharging of the resin for water softening;
TEST DE FINAL DE LABORATOR
Analiza apei
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Putem spune urmatoarele:
- apa naturala poate contine materie organica si organisme vii;
- purificarea apei poate include procedee fizice;
- apa este pura doar atunci cānd este luata dintr-un bun izvor de munte de apa dulce;
- apa este un solvent polar bun;
- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru aciditate minerala:
- NaOH + Cl- -> NaCl + HO-
- NaOH + SO42- -> Na2SO4 + HO-
- NaOH + Cl+ -> NaCl + HO+
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + SO42+ -> Na2SO4 + HO+
- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru alcalinitate totala:
- HCl + CO32+ -> H2CO3 + Cl+
- HCl + HO- -> H2O + Cl-
- HCl + PO43+ -> H2PO4+ + Cl+
- HCl + HO+ -> H2O + Cl+
- In laborator apa au fost:
- complexata prin metoda titrimetrica EDTA;
- dedurizata folosind coloana de rasina;
- acidulata pentru baut;
- calita folosind coloana de rasina;
- alcalinizeaza pentru baut;
- EDTA este utilizat:
- pentru complexarea ionilor de Ca2 +si Mg2 +;
- pentru complexarea ionilor de Na1 +si K1 +;
- ca reactiv pentru determinarea duritatii apei;
- pentru reīncarcarea rasinii la dedurizarea apei;
- ca masura de siguranta;
FINAL TEST AT LABORATORY
Water analysis
Do not use this paper to give answers!
Please decide which of the following statements are true.- Following reactions may tok place when we analyse a sample of water for total alkalinity:
- HCl + HO+ -> H2O + Cl+
- HCl + CO32- -> H2CO3 + Cl-
- HCl + HO- -> H2O + Cl-
- NaOH + Ni2+ -> Ni(OH)2 + Na+
- Following reactions may tok place when we analyse a sample of water for mineral acidity:
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + SO42- -> Na2SO4 + HO-
- NaOH + NO3+ -> NaNO3 + HO+
- NaOH + Cl- -> NaCl + HO-
- Following reactions may tok place when we analyse a sample of water for partial alkalinity:
- HCl + HO- -> H2O + Cl-
- NaOH + Fe2+ -> Fe(OH)2 + Na+
- HCl + HO+ -> H2O + Cl+
- HCl + PO43- -> HPO42- + Cl-
- We may say the followings:
- purification of the water may include labeling processes;
- purification of the water may include biological processes;
- water is good for drinking, it is nothing to be analysed;
- purification of the water may include physical processes;
- For a water sample following measures may be quantitatively expressed:
- mineral acidity;
- purity;
- total acidity;
- total alkalinity;
TEST DE FINAL DE LABORATOR
Analiza apei
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru alcalinitate totala:
- HCl + HO+ -> H2O + Cl+
- HCl + CO32- -> H2CO3 + Cl-
- HCl + HO- -> H2O + Cl-
- NaOH + Ni2+ -> Ni(OH)2 + Na+
- HCl + CO32+ -> H2CO3 + Cl+
- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru aciditate minerala:
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + SO42- -> Na2SO4 + HO-
- NaOH + NO3+ -> NaNO3 + HO+
- NaOH + Cl- -> NaCl + HO-
- NaOH + Cl+ -> NaCl + HO+
- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru alcalinitate partiala:
- HCl + HO- -> H2O+Cl-
- NaOH + Fe2+ -> Fe(OH)2 + Na+
- HCl + HO+ -> H2O + Cl+
- HCl + PO43- -> HPO42- + Cl-
- HCl + CO32+ -> HCO3+ + Cl+
- Putem spune urmatoarele:
- purificarea apei poate include procesele de etichetare;
- purificarea apei poate include procese biologice;
- apa este buna pentru consum, nu este nimic de a fi analizat;
- purificarea apei poate include procedee fizice;
- atunci cānd apa contine minerale dizolvate si gaze este rea pentru baut;
- Pentru o proba de apa urmatoarele masuri pot fi exprimate cantitativ:
- aciditate minerala;
- puritate;
- aciditate totala;
- alcalinitate totala;
FINAL TEST AT LABORATORY
Water analysis
Do not use this paper to give answers!
Please decide which of the following statements are true.- In the laboratory the water were:
- complexed by using EDTA titrimetric method;
- alkalinized for drinking purposes;
- hardened using the resin column;
- biologically purified using the resin column;
- Following reactions may tok place when we analyse a sample of water for mineral acidity:
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + Zn2+ -> Zn(OH)2 + Na+
- NaOH + Cl- -> NaCl + HO-
- NaOH + NO3+ -> NaNO3 + HO+
- For a water sample following measures may be quantitatively expressed:
- total acidity;
- purity;
- hardness;
- permanent alkalinity;
- We may say the followings:
- water is a good polar solvent;
- natural water may contain organic matter and living organisms;
- purification of the water may include physical processes;
- water is good for drinking, it is nothing to be analysed;
- EDTA is used:
- for recharging of the resin for water softening;
- for complexing of Ca2+ and Mg2+ ions;
- for indication of the equilibrium point in the reaction;
- for safety precautions purposes;
TEST DE FINAL DE LABORATOR
Analiza apei
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- In laborator apa au fost:
- complexata prin metoda titrimetrica EDTA;
- alcalinizeaza pentru baut;
- calita folosind coloana de rasina;
- purificata biologic utilizānd coloana de rasina;
- dedurizata folosind coloana de rasina;
- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru aciditate minerala:
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + Zn2+ -> Zn(OH)2 + Na+
- NaOH + Cl- -> NaCl + HO-
- NaOH + NO3+ -> NaNO3 + HO+
- NaOH + SO42- -> Na2SO4 + HO-
- Pentru o proba de apa urmatoarele masuri pot fi exprimate cantitativ:
- aciditate totala;
- puritate;
- duritate;
- alcalinitate permanenta;
- Putem spune urmatoarele:
- apa este un solvent polar bun;
- apa naturala poate contine materie organica si organisme vii;
- purificarea apei poate include procedee fizice;
- apa este buna pentru consum, nu este nimic de a fi analizat;
- purificarea apei poate include procesele de etichetare;
- EDTA este utilizat:
- pentru reīncarcarea rasinii la dedurizarea apei;
- pentru complexarea ionilor de Ca2 +si Mg2 +;
- pentru indicarea punctului de echilibru īn reactie;
- ca masura de siguranta;
FINAL TEST AT LABORATORY
Water analysis
Do not use this paper to give answers!
Please decide which of the following statements are true.- Following reactions may tok place when we analyse a sample of water for partial alkalinity:
- HCl + HO- -> H2O + Cl-
- HCl + CO32- -> HCO3- + Cl-
- NaOH + Fe2+ -> Fe(OH)2 + Na+
- HCl + PO43+ -> HPO42+ + Cl+
- Following reactions may tok place when we analyse a sample of water for mineral acidity:
- NaOH + Zn2+ -> Zn(OH)2 + Na+
- NaOH + SO42- -> Na2SO4 + HO-
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + Cl+ -> NaCl + HO+
- In the laboratory were analyzed:
- the softness of the water;
- the temperature of the water;
- the boiling point of the water;
- the hardness of the water;
- We may say the followings:
- purification of the water may include chemical processes;
- purification of the water may include physical processes;
- when water contains dissolved minerals and gases is bad for drinking;
- water is a good polar solvent;
- EDTA is used:
- for safety precautions purposes;
- as reagent for determining the hardness of the water;
- for complexing of Ca2+ and Mg2+ ions;
- for recharging of the resin for water softening;
TEST DE FINAL DE LABORATOR
Analiza apei
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru alcalinitate partiala:
- HCl + HO- -> H2O+Cl-
- HCl + CO32- -> HCO3- + Cl-
- NaOH + Fe2+ -> Fe(OH)2 + Na+
- HCl + PO43+ -> HPO42+ + Cl+
- Urmatoarele reactii pot avea loc atunci cānd analizam un esantion de apa pentru aciditate minerala:
- NaOH + Zn2+ -> Zn(OH)2 + Na+
- NaOH + SO42- -> Na2SO4 + HO-
- NaOH + NO3- -> NaNO3 + HO-
- NaOH + Cl+ -> NaCl + HO+
- NaOH + SO42+ -> Na2SO4 + HO+
- Īn laborator au fost analizate:
- moliciunea apei;
- temperatura apei;
- punctul de fierbere al apei;
- duritatea apei;
- concentratia apei;
- Putem spune urmatoarele:
- purificarea apei poate include procese chimice;
- purificarea apei poate include procedee fizice;
- atunci cānd apa contine minerale dizolvate si gaze este rea pentru baut;
- apa este un solvent polar bun;
- apa naturala poate contine materie organica si organisme vii;
- EDTA este utilizat:
- ca masura de siguranta;
- ca reactiv pentru determinarea duritatii apei;
- pentru complexarea ionilor de Ca2 +si Mg2 +;
- pentru reīncarcarea rasinii la dedurizarea apei;
- pentru complexarea ionilor de Na1 +si K1 +;
FINAL TEST AT LABORATORY
Volumetric and gravimetric methods in study of corrosion
Do not use this paper to give answers!
Please decide which of the following statements are true.- The aluminum plate:
- was involved in the volumetric method of corrosion analysis
- was corroded in sodium hydroxide solution;
- the volume is measured before and after immersing it in NaOH;
- was degreased in sodium hydroxide solution;
- The zinc plate:
- the surface is measured before and after immersing it in H2SO4;
- was involved in the volumetric method of corrosion analysis
- was degreased in sulfuric acid solution;
- was corroded in sulfuric solution;
- Corrosion of metals:
- is a beneficial process that shows the stability of metals;
- takes place merely from exposure to moisture in air;
- is the protection in time to chemical agents;
- can be reduced by electroplating;
- In studied corrosion processes:
- the metal it changes its oxidation state becoming an anion;
- a gas is released only the corrosion of aluminum;
- a gas is released only the corrosion of zinc;
- the metal it changes its oxidation state becoming an cation;
- Which of the following reactions may be called as of corrosion:
- Ni(CO)4 -> Ni + CO
- H+ + Fe -> H2 + Fe2+
- ZnO + H2SO4 -> ZnSO4 + H2O
- Al2O3 + NaOH -> NaAlO2
TEST DE FINAL DE LABORATOR
Metode volumetrice si gravimetrice in studiul coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Pentru placa de aluminiu:
- a fost implicata īn metoda volumetrica de analiza a coroziunii
- a fost corodata īn solutie de hidroxid de sodiu;
- volumul se masoara īnainte si dupa imersia īn NaOH;
- a fost degresata īn solutie de hidroxid de sodiu;
- Pentru placa de zinc:
- suprafata se masoara īnainte si dupa imersia īn H2SO4;
- a fost implicata īn metoda volumetrica de analiza a coroziunii
- a fost degresata īn solutie de acid sulfuric;
- a fost corodata īn solutie sulfuric;
- masa este masurata īnainte si dupa imersia īn H2SO4;
- Coroziunea metalelor:
- este un proces benefic care arata stabilitatea metalelor;
- are loc pur si simplu prin expunerea la umiditate īn aer;
- este protectia de durata impotriva agentilor chimici;
- poate fi redusa prin galvanizare;
- poate furniza materii prime utile pentru analiza;
- Īn procesele de coroziune studiate:
- metalul isi schimba starea de oxidare pentru a deveni un anion;
- un gaz este eliberat numai la corodarea aluminiului;
- un gaz este eliberat numai la corodarea zincului;
- metalul isi schimba starea de oxidare pentru a deveni un cation;
- atunci cānd un gaz este eliberat volumul sau depinde de cantitatea de metal corodat;
- Care dintre urmatoarele reactii pot fi numite ca fiind de coroziune:
- Ni(CO)4 -> Ni + CO
- H+ + Fe -> H2 + Fe2+
- ZnO + H2SO4 -> ZnSO4 + H2O
- Al2O3 + NaOH -> NaAlO2
- Fe2O3 + CO -> Fe + CO2
FINAL TEST AT LABORATORY
Volumetric and gravimetric methods in study of corrosion
Do not use this paper to give answers!
Please decide which of the following statements are true.- Corrosion of metals:
- is the destruction of metals under the action of external factors;
- is a beneficial process that shows the stability of metals;
- takes place merely from exposure to moisture in air;
- can be reduced by electroplating;
- The aluminum plate:
- the surface is measured before and after immersing it in NaOH;
- was involved in the gravimetric method of corrosion analysis
- is expected to have approximately the same mass at the end of the semester as at the beginning of it;
- was degreased in sodium hydroxide solution;
- In studied corrosion processes:
- always the metal changes its oxidation state;
- a gas is released at both corrosion of zinc and aluminum;
- a gas is released only the corrosion of zinc;
- the metal it changes its oxidation state becoming an anion;
- The zinc plate:
- the surface is measured before and after immersing it in H2SO4;
- was involved in the gravimetric method of corrosion analysis
- the volume is measured before and after immersing it in H2SO4;
- was degreased in sulfuric acid solution;
- Which of the following reactions may be called as of corrosion:
- H+ + Zn -> H2 + Zn2+
- H2O + HO- + Al -> H2 + Al(OH)4-
- H+ + Ni -> H2 + Ni2+
- ZnO + CO -> Zn + CO2
TEST DE FINAL DE LABORATOR
Metode volumetrice si gravimetrice in studiul coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Coroziunea metalelor:
- este distrugerea metalelor sub actiunea factorilor externi;
- este un proces benefic care arata stabilitatea metalelor;
- are loc pur si simplu prin expunerea la umiditate īn aer;
- poate fi redusa prin galvanizare;
- este de ajutor īn procesul de curatare a suprafetelor metalelor;
- Pentru placa de aluminiu:
- suprafata se masoara īnainte si dupa imersia īn NaOH;
- a fost implicata īn metoda gravimetrica de analiza a coroziunii
- este de asteptat sa aiba aproximativ aceeasi masa la sfārsitul semestrului ca la īnceputul acestuia;
- a fost degresata īn solutie de hidroxid de sodiu;
- a fost corodata īn solutie de hidroxid de sodiu;
- Īn procesele de coroziune studiate:
- īntotdeauna metalul isi schimba starea de oxidare;
- un gaz este eliberat la ambele coroziuni ale zincului si aluminiului;
- un gaz este eliberat numai la corodarea zincului;
- metalul isi schimba starea de oxidare pentru a deveni un anion;
- Pentru placa de zinc:
- suprafata se masoara īnainte si dupa imersia īn H2SO4;
- a fost implicata īn metoda gravimetrica de analiza a coroziunii
- volumul se masoara īnainte si dupa imersia īn H2SO4;
- a fost degresata īn solutie de acid sulfuric;
- Care dintre urmatoarele reactii pot fi numite ca fiind de coroziune:
- H+ + Zn -> H2 + Zn2+
- H2O + HO- + Al -> H2 + Al(OH)4-
- H+ + Ni -> H2 + Ni2+
- ZnO + CO -> Zn + CO2
- H+ + Fe -> H2 + Fe2+
FINAL TEST AT LABORATORY
Volumetric and gravimetric methods in study of corrosion
Do not use this paper to give answers!
Please decide which of the following statements are true.- In studied corrosion processes:
- when a gas is released its volume depends on the amount of metal corroded;
- a gas is released only the corrosion of zinc;
- a gas is released at both corrosion of zinc and aluminum;
- always the metal changes its oxidation state;
- The zinc plate:
- the mass is measured before and after immersing it in H2SO4;
- is expected to have approximately the same mass at the end of the semester as at the beginning of it;
- was involved in the gravimetric method of corrosion analysis
- was degreased in sulfuric acid solution;
- Corrosion of metals:
- is helping in the process of cleaning the metals surfaces;
- can be reduced by electroplating;
- may provide useful raw materials for analysis;
- is the protection in time to chemical agents;
- The aluminum plate:
- was degreased in sodium hydroxide solution;
- the surface is measured before and after immersing it in NaOH;
- was involved in the volumetric method of corrosion analysis
- was corroded in sodium hydroxide solution;
- Which of the following reactions may be called as of corrosion:
- Al2O3 + NaOH -> NaAlO2
- Ni(CO)4 -> Ni + CO
- Fe2O3 + CO -> Fe + CO2
- H2O + HO- + Al -> H2 + Al(OH)4-
TEST DE FINAL DE LABORATOR
Metode volumetrice si gravimetrice in studiul coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Īn procesele de coroziune studiate:
- atunci cānd un gaz este eliberat volumul sau depinde de cantitatea de metal corodat;
- un gaz este eliberat numai la corodarea zincului;
- un gaz este eliberat la ambele coroziuni ale zincului si aluminiului;
- īntotdeauna metalul isi schimba starea de oxidare;
- metalul isi schimba starea de oxidare pentru a deveni un cation;
- Pentru placa de zinc:
- masa este masurata īnainte si dupa imersia īn H2SO4;
- este de asteptat sa aiba aproximativ aceeasi masa la sfārsitul semestrului ca la īnceputul acestuia;
- a fost implicata īn metoda gravimetrica de analiza a coroziunii
- a fost degresata īn solutie de acid sulfuric;
- Coroziunea metalelor:
- este de ajutor īn procesul de curatare a suprafetelor metalelor;
- poate fi redusa prin galvanizare;
- poate furniza materii prime utile pentru analiza;
- este protectia de durata impotriva agentilor chimici;
- este un proces benefic care arata stabilitatea metalelor;
- Pentru placa de aluminiu:
- a fost degresata īn solutie de hidroxid de sodiu;
- suprafata se masoara īnainte si dupa imersia īn NaOH;
- a fost implicata īn metoda volumetrica de analiza a coroziunii
- a fost corodata īn solutie de hidroxid de sodiu;
- Care dintre urmatoarele reactii pot fi numite ca fiind de coroziune:
- Al2O3 + NaOH -> NaAlO2
- Ni(CO)4 -> Ni + CO
- Fe2O3 + CO -> Fe + CO2
- H2O + HO- + Al -> H2 + Al(OH)4-
FINAL TEST AT LABORATORY
Volumetric and gravimetric methods in study of corrosion
Do not use this paper to give answers!
Please decide which of the following statements are true.- The zinc plate:
- was corroded in sulfuric solution;
- was degreased in sulfuric acid solution;
- was involved in the gravimetric method of corrosion analysis
- the mass is measured before and after immersing it in H2SO4;
- In studied corrosion processes:
- a gas is released at both corrosion of zinc and aluminum;
- when a gas is released its volume depends on the amount of metal corroded;
- always the metal changes its oxidation state;
- a gas is released only the corrosion of aluminum;
- Corrosion of metals:
- is the protection in time to chemical agents;
- is helping in the process of cleaning the metals surfaces;
- may provide useful raw materials for analysis;
- can be reduced by passivation;
- The aluminum plate:
- the mass is measured before and after immersing it in NaOH;
- was degreased in sodium hydroxide solution;
- was involved in the gravimetric method of corrosion analysis
- the surface is measured before and after immersing it in NaOH;
- Which of the following reactions may be called as of corrosion:
- H+ + Fe -> H2 + Fe2+
- H2O + HO- + Al -> H2 + Al(OH)4-
- Fe2O3 + CO -> Fe + CO2
- Al2O3 + NaOH -> NaAlO2
TEST DE FINAL DE LABORATOR
Metode volumetrice si gravimetrice in studiul coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Pentru placa de zinc:
- a fost corodata īn solutie sulfuric;
- a fost degresata īn solutie de acid sulfuric;
- a fost implicata īn metoda gravimetrica de analiza a coroziunii
- masa este masurata īnainte si dupa imersia īn H2SO4;
- Īn procesele de coroziune studiate:
- un gaz este eliberat la ambele coroziuni ale zincului si aluminiului;
- atunci cānd un gaz este eliberat volumul sau depinde de cantitatea de metal corodat;
- īntotdeauna metalul isi schimba starea de oxidare;
- un gaz este eliberat numai la corodarea aluminiului;
- metalul isi schimba starea de oxidare pentru a deveni un anion;
- Coroziunea metalelor:
- este protectia de durata impotriva agentilor chimici;
- este de ajutor īn procesul de curatare a suprafetelor metalelor;
- poate furniza materii prime utile pentru analiza;
- poate fi redusa prin pasivare;
- este distrugerea metalelor sub actiunea factorilor externi;
- Pentru placa de aluminiu:
- masa este masurata īnainte si dupa imersia īn NaOH;
- a fost degresata īn solutie de hidroxid de sodiu;
- a fost implicata īn metoda gravimetrica de analiza a coroziunii
- suprafata se masoara īnainte si dupa imersia īn NaOH;
- a fost corodata īn solutie de hidroxid de sodiu;
- Care dintre urmatoarele reactii pot fi numite ca fiind de coroziune:
- H+ + Fe -> H2 + Fe2+
- H2O + HO- + Al -> H2 + Al(OH)4-
- Fe2O3 + CO -> Fe + CO2
- Al2O3 + NaOH -> NaAlO2
FINAL TEST AT LABORATORY
Volumetric and gravimetric methods in study of corrosion
Do not use this paper to give answers!
Please decide which of the following statements are true.- The zinc plate:
- the mass is measured before and after immersing it in H2SO4;
- the volume is measured before and after immersing it in H2SO4;
- was involved in the volumetric method of corrosion analysis
- is expected to have approximately the same mass at the end of the semester as at the beginning of it;
- Corrosion of metals:
- may provide useful raw materials for analysis;
- is helping in the process of cleaning the metals surfaces;
- is the protection in time to chemical agents;
- can be reduced by passivation;
- Which of the following reactions may be called as of corrosion:
- Ni(CO)4 -> Ni + CO
- ZnO + CO -> Zn + CO2
- H+ + Ni -> H2 + Ni2+
- Fe2O3 + CO -> Fe + CO2
- The aluminum plate:
- is expected to have approximately the same mass at the end of the semester as at the beginning of it;
- was involved in the volumetric method of corrosion analysis
- the volume is measured before and after immersing it in NaOH;
- was corroded in sodium hydroxide solution;
- In studied corrosion processes:
- always the metal changes its oxidation state;
- the metal it changes its oxidation state becoming an anion;
- when a gas is released its volume depends on the amount of metal corroded;
- a gas is released only the corrosion of zinc;
TEST DE FINAL DE LABORATOR
Metode volumetrice si gravimetrice in studiul coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Pentru placa de zinc:
- masa este masurata īnainte si dupa imersia īn H2SO4;
- volumul se masoara īnainte si dupa imersia īn H2SO4;
- a fost implicata īn metoda volumetrica de analiza a coroziunii
- este de asteptat sa aiba aproximativ aceeasi masa la sfārsitul semestrului ca la īnceputul acestuia;
- a fost corodata īn solutie sulfuric;
- Coroziunea metalelor:
- poate furniza materii prime utile pentru analiza;
- este de ajutor īn procesul de curatare a suprafetelor metalelor;
- este protectia de durata impotriva agentilor chimici;
- poate fi redusa prin pasivare;
- Care dintre urmatoarele reactii pot fi numite ca fiind de coroziune:
- Ni(CO)4 -> Ni + CO
- ZnO + CO -> Zn + CO2
- H+ + Ni -> H2 + Ni2+
- Fe2O3 + CO -> Fe + CO2
- Al2O3 + NaOH -> NaAlO2
- Pentru placa de aluminiu:
- este de asteptat sa aiba aproximativ aceeasi masa la sfārsitul semestrului ca la īnceputul acestuia;
- a fost implicata īn metoda volumetrica de analiza a coroziunii
- volumul se masoara īnainte si dupa imersia īn NaOH;
- a fost corodata īn solutie de hidroxid de sodiu;
- a fost implicata īn metoda gravimetrica de analiza a coroziunii
- Īn procesele de coroziune studiate:
- īntotdeauna metalul isi schimba starea de oxidare;
- metalul isi schimba starea de oxidare pentru a deveni un anion;
- atunci cānd un gaz este eliberat volumul sau depinde de cantitatea de metal corodat;
- un gaz este eliberat numai la corodarea zincului;
- metalul isi schimba starea de oxidare pentru a deveni un cation;
FINAL TEST AT LABORATORY
Nickel corrosion protective electroplating
Do not use this paper to give answers!
Please decide which of the following statements are true.- At the nickel plating following reactions took place:
- at high densities of current oxygen anions (O2-) have the tendency to discharge at the cathode: O2- - 2e- -> O20
- at anode (+), connected with nickel piece, Ni2+ + 2e- -> Ni0
- at anode (+), connected with nickel piece, Ni0 - 2e- -> Ni2+
- at cathode (-), connected with metallic piece, Ni0 - 2e- -> Ni2+
- The intensity of the current:
- affect only the quality of the nickel deposition;
- affect only the quantity of the nickel deposition;
- does not affect the quality nor the quantity of the nickel deposition;
- is to be adjusted when the experiment starts;
- Electrical conductivity of nickel salts solutions:
- is improved by salts additions;
- is relatively small;
- is relatively high;
- depends on the intensity of the current used;
- It is expected to have a mass of nickel deposited:
- proportional with the nickel plating time;
- inversely proportional with the nickel plating time;
- higher than the calculated theoretical one;
- lower than the calculated theoretical one;
- Theoretical mass of nickel deposited is calculated using:
- the conservation of the energy law;
- law of mass action;
- solutions laws;
- the conservation of the number of atoms for each element law;
TEST DE FINAL DE LABORATOR
Electrodepunerea nichelului protectiva impotriva coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- La nichelare urmatoarele reactii au avut loc:
- la densitati mari de curent anionii de oxigen (O2-) au tendinta de a descarca la catod: O2- - 2e- -> O20
- la anod (+), īn legatura cu piesa de nichel, Ni2+ + 2e- -> Ni0
- la anod (+), īn contact cu piesa de nichel, Ni0 - 2e- -> Ni2+
- la catod (-), īn legatura cu piesa metalica, Ni0 - 2e- -> Ni2+
- la densitati mari de curent anionii de oxigen (O2-) au tendinta de a descarca la anod: O2- - 2e- -> O20
- Intensitatea curentului:
- afecteaza numai calitatea depunerii nichelului;
- afecteaza numai cantitatea de nichel depus;
- nu afecteaza calitatea nici cantitatea nichelului depus;
- trebuie sa fie ajustata cand se incepe experimentul;
- Conductivitatea electrica a solutiilor de saruri de nichel:
- este īmbunatatita prin adaosuri de saruri;
- este relativ mica;
- este relativ mare;
- depinde de intensitatea curentului utilizat;
- este redusa prin adaosuri de saruri;
- Este de asteptat ca masa de nichel depus sa fie:
- proportionala cu timpul de nichelare;
- invers proportional cu timpul de nichelare;
- mai mare decāt cea teoretica calculata;
- mai mica decāt cea teoretica calculata;
- Masa teoretica de nichel depus se calculeaza folosind:
- legea conservarii energiei;
- legea actiunii maselor;
- legea solutilor;
- conservarea numarului de atomi pentru fiecare element;
FINAL TEST AT LABORATORY
Nickel corrosion protective electroplating
Do not use this paper to give answers!
Please decide which of the following statements are true.- Electrical conductivity of nickel salts solutions:
- is relatively high;
- depends on the potential of the source used;
- is reduced by salts additions;
- is relatively small;
- The intensity of the current:
- does not affect the quality nor the quantity of the nickel deposition;
- affect only the quantity of the nickel deposition;
- is to be calculated before to start the experiment;
- is to be calculated after conducting the experiment;
- At the nickel plating following reactions took place:
- at anode (+), connected with nickel piece, Ni2+ + 2e- -> Ni0
- at high densities of current oxygen anions (O2-) have the tendency to discharge at the anode: O2- - 2e- -> O20
- at cathode (-), connected with metallic piece, Ni2+ + 2e- -> Ni0
- at anode (+), connected with nickel piece, Ni0 - 2e- -> Ni2+
- Theoretical mass of nickel deposited is calculated using:
- the electrolysis law;
- the conservation of the number of atoms for each element law;
- law of mass action;
- the conservation of the energy law;
- It is expected to have a mass of nickel deposited:
- proportional with the surface of the sample;
- inversely proportional with the nickel plating time;
- much lower than the calculated theoretical one;
- inversely proportional with the surface of the sample;
TEST DE FINAL DE LABORATOR
Electrodepunerea nichelului protectiva impotriva coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Conductivitatea electrica a solutiilor de saruri de nichel:
- este relativ mare;
- depinde de potentialul sursei utilizate;
- este redusa prin adaosuri de saruri;
- este relativ mica;
- Intensitatea curentului:
- nu afecteaza calitatea nici cantitatea nichelului depus;
- afecteaza numai cantitatea de nichel depus;
- trebuie sa fie calculata īnainte de a īncepe experimentul;
- se calculeaza dupa efectuarea experimentului;
- La nichelare urmatoarele reactii au avut loc:
- la anod (+), īn legatura cu piesa de nichel, Ni2+ + 2e- -> Ni0
- la densitati mari de curent anionii de oxigen (O2-) au tendinta de a descarca la anod: O2- - 2e- -> O20
- la catod (-), īn contact cu piesa metalica, Ni2+ + 2e- -> Ni0
- la anod (+), īn contact cu piesa de nichel, Ni0 - 2e- -> Ni2+
- Masa teoretica de nichel depus se calculeaza folosind:
- legea electrolizei;
- conservarea numarului de atomi pentru fiecare element;
- legea actiunii maselor;
- legea conservarii energiei;
- legea solutilor;
- Este de asteptat ca masa de nichel depus sa fie:
- proportionala cu suprafata probei;
- invers proportional cu timpul de nichelare;
- mult mai mica decāt cea teoretica calculata;
- invers proportionala cu suprafata probei;
- mai mica decāt cea teoretica calculata;
FINAL TEST AT LABORATORY
Nickel corrosion protective electroplating
Do not use this paper to give answers!
Please decide which of the following statements are true.- It is expected to have a mass of nickel deposited:
- inversely proportional with the nickel plating time;
- higher than the calculated theoretical one;
- much lower than the calculated theoretical one;
- much higher than the calculated theoretical one;
- At the nickel plating following reactions took place:
- at cathode (-), connected with metallic piece, Ni2+ + 2e- -> Ni0
- at high densities of current oxygen anions (O2-) have the tendency to discharge at the anode: O2- - 2e- -> O20
- at high densities of current oxygen anions (O2-) have the tendency to discharge at the cathode: O2- - 2e- -> O20
- at cathode (-), connected with metallic piece, Ni0 - 2e- -> Ni2+
- Theoretical mass of nickel deposited is calculated using:
- the conservation of the energy law;
- perfect gas law;
- the conservation of the number of atoms for each element law;
- law of mass action;
- The intensity of the current:
- does not affect the quality nor the quantity of the nickel deposition;
- is to be calculated after conducting the experiment;
- affect only the quality of the nickel deposition;
- is to be calculated before to start the experiment;
- Electrical conductivity of nickel salts solutions:
- is relatively high;
- depends on the intensity of the current used;
- is reduced by salts additions;
- depends on the potential of the source used;
TEST DE FINAL DE LABORATOR
Electrodepunerea nichelului protectiva impotriva coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Este de asteptat ca masa de nichel depus sa fie:
- invers proportional cu timpul de nichelare;
- mai mare decāt cea teoretica calculata;
- mult mai mica decāt cea teoretica calculata;
- mult mai mare decāt cea teoretica calculata;
- proportionala cu intensitatea curentului utilizat;
- La nichelare urmatoarele reactii au avut loc:
- la catod (-), īn contact cu piesa metalica, Ni2+ + 2e- -> Ni0
- la densitati mari de curent anionii de oxigen (O2-) au tendinta de a descarca la anod: O2- - 2e- -> O20
- la densitati mari de curent anionii de oxigen (O2-) au tendinta de a descarca la catod: O2- - 2e- -> O20
- la catod (-), īn legatura cu piesa metalica, Ni0 - 2e- -> Ni2+
- la anod (+), īn contact cu piesa de nichel, Ni0 - 2e- -> Ni2+
- Masa teoretica de nichel depus se calculeaza folosind:
- legea conservarii energiei;
- legea gazelor perfecte;
- conservarea numarului de atomi pentru fiecare element;
- legea actiunii maselor;
- Intensitatea curentului:
- nu afecteaza calitatea nici cantitatea nichelului depus;
- se calculeaza dupa efectuarea experimentului;
- afecteaza numai calitatea depunerii nichelului;
- trebuie sa fie calculata īnainte de a īncepe experimentul;
- Conductivitatea electrica a solutiilor de saruri de nichel:
- este relativ mare;
- depinde de intensitatea curentului utilizat;
- este redusa prin adaosuri de saruri;
- depinde de potentialul sursei utilizate;
FINAL TEST AT LABORATORY
Nickel corrosion protective electroplating
Do not use this paper to give answers!
Please decide which of the following statements are true.- At the nickel plating following reactions took place:
- at high densities of current oxygen anions (O2-) have the tendency to discharge at the cathode: O2- - 2e- -> O20
- at anode (+), connected with nickel piece, Ni0 - 2e- -> Ni2+
- at cathode (-), connected with metallic piece, Ni0 - 2e- -> Ni2+
- at cathode (-), connected with metallic piece, Ni2+ + 2e- -> Ni0
- The intensity of the current:
- is to be calculated after conducting the experiment;
- does not affect the quality nor the quantity of the nickel deposition;
- affect only the quality of the nickel deposition;
- is to be adjusted when the experiment starts;
- Theoretical mass of nickel deposited is calculated using:
- solutions laws;
- the electrolysis law;
- perfect gas law;
- law of mass action;
- Electrical conductivity of nickel salts solutions:
- is reduced by salts additions;
- depends on the potential of the source used;
- is improved by salts additions;
- depends on the intensity of the current used;
- It is expected to have a mass of nickel deposited:
- inversely proportional with the intensity of the current used;
- higher than the calculated theoretical one;
- proportional with the intensity of the current used;
- proportional with the surface of the sample;
TEST DE FINAL DE LABORATOR
Electrodepunerea nichelului protectiva impotriva coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- La nichelare urmatoarele reactii au avut loc:
- la densitati mari de curent anionii de oxigen (O2-) au tendinta de a descarca la catod: O2- - 2e- -> O20
- la anod (+), īn contact cu piesa de nichel, Ni0 - 2e- -> Ni2+
- la catod (-), īn legatura cu piesa metalica, Ni0 - 2e- -> Ni2+
- la catod (-), īn contact cu piesa metalica, Ni2+ + 2e- -> Ni0
- la anod (+), īn legatura cu piesa de nichel, Ni2+ + 2e- -> Ni0
- Intensitatea curentului:
- se calculeaza dupa efectuarea experimentului;
- nu afecteaza calitatea nici cantitatea nichelului depus;
- afecteaza numai calitatea depunerii nichelului;
- trebuie sa fie ajustata cand se incepe experimentul;
- Masa teoretica de nichel depus se calculeaza folosind:
- legea solutilor;
- legea electrolizei;
- legea gazelor perfecte;
- legea actiunii maselor;
- conservarea numarului de atomi pentru fiecare element;
- Conductivitatea electrica a solutiilor de saruri de nichel:
- este redusa prin adaosuri de saruri;
- depinde de potentialul sursei utilizate;
- este īmbunatatita prin adaosuri de saruri;
- depinde de intensitatea curentului utilizat;
- este relativ mica;
- Este de asteptat ca masa de nichel depus sa fie:
- invers proportionala cu intensitatea curentului utilizat;
- mai mare decāt cea teoretica calculata;
- proportionala cu intensitatea curentului utilizat;
- proportionala cu suprafata probei;
- mai mica decāt cea teoretica calculata;
FINAL TEST AT LABORATORY
Nickel corrosion protective electroplating
Do not use this paper to give answers!
Please decide which of the following statements are true.- It is expected to have a mass of nickel deposited:
- inversely proportional with the surface of the sample;
- inversely proportional with the intensity of the current used;
- inversely proportional with the nickel plating time;
- much lower than the calculated theoretical one;
- At the nickel plating following reactions took place:
- at cathode (-), connected with metallic piece, Ni0 - 2e- -> Ni2+
- at anode (+), connected with nickel piece, Ni2+ + 2e- -> Ni0
- at cathode (-), connected with metallic piece, Ni2+ + 2e- -> Ni0
- at high densities of current oxygen anions (O2-) have the tendency to discharge at the cathode: O2- - 2e- -> O20
- Electrical conductivity of nickel salts solutions:
- is improved by salts additions;
- depends on the intensity of the current used;
- is reduced by salts additions;
- is relatively small;
- Theoretical mass of nickel deposited is calculated using:
- perfect gas law;
- law of mass action;
- solutions laws;
- the conservation of the number of atoms for each element law;
- The intensity of the current:
- is to be calculated after conducting the experiment;
- it depends on the surface of the sample;
- should be adjusted by the technicians, we have nothing to do there;
- affect only the quantity of the nickel deposition;
TEST DE FINAL DE LABORATOR
Electrodepunerea nichelului protectiva impotriva coroziunii
Nu utilizati aceasta hartie pentru a da raspunsurile!
Va rog decideti care dintre urmatoarele afirmatii sunt corecte.- Este de asteptat ca masa de nichel depus sa fie:
- invers proportionala cu suprafata probei;
- invers proportionala cu intensitatea curentului utilizat;
- invers proportional cu timpul de nichelare;
- mult mai mica decāt cea teoretica calculata;
- mult mai mare decāt cea teoretica calculata;
- La nichelare urmatoarele reactii au avut loc:
- la catod (-), īn legatura cu piesa metalica, Ni0 - 2e- -> Ni2+
- la anod (+), īn legatura cu piesa de nichel, Ni2+ + 2e- -> Ni0
- la catod (-), īn contact cu piesa metalica, Ni2+ + 2e- -> Ni0
- la densitati mari de curent anionii de oxigen (O2-) au tendinta de a descarca la catod: O2- - 2e- -> O20
- Conductivitatea electrica a solutiilor de saruri de nichel:
- este īmbunatatita prin adaosuri de saruri;
- depinde de intensitatea curentului utilizat;
- este redusa prin adaosuri de saruri;
- este relativ mica;
- Masa teoretica de nichel depus se calculeaza folosind:
- legea gazelor perfecte;
- legea actiunii maselor;
- legea solutilor;
- conservarea numarului de atomi pentru fiecare element;
- Intensitatea curentului:
- se calculeaza dupa efectuarea experimentului;
- depinde de suprafata probei;
- ar trebui sa fie ajustata de catre tehnicieni, nu avem nimic de a face acolo;
- afecteaza numai cantitatea de nichel depus;