Equilibrium Mock Test – Class 11 Chemistry

1. For the same pure liquid in a closed vessel, vapour pressure at equilibrium is higher at than at because

2. A mixed aqueous system contains a weak acid , its salt , and a sparingly soluble salt . The ion is important because it is

3. At , a solution has . Its is

4. A weak acid solution has and . Using , the is

5. A concentration-time graph is drawn for the same reversible reaction with and without a catalyst. The catalysed graph should show

6. The reaction represents a homogeneous equilibrium because

7. The pair and is a conjugate acid-base pair because

8. The equilibrium is best classified as

9. An acidic buffer contains and . If and , the is closest to

10. A solution of at is treated as a strong base. Its is

11. A short reaction record is given: a colourless gas mixture slowly becomes brown in a sealed tube and then the colour intensity remains unchanged. The brown colour is due to one component of a reversible chemical system. The unchanged final colour most strongly suggests that

12. can act as a Lewis base because it has

13. A weak acid approximation gives for a acid. The percent ionization is

14. In the pair and , the charge change supports the idea that

15. The statement “a solution with is always acidic” is incomplete because

16. A sealed reaction vessel contains at equilibrium. The brown colour due to remains constant. This constant colour most directly indicates that

17. A mixture for has current concentrations and . If , the system will initially shift

18. A larger value of for two weak acids at the same temperature means that the acid with larger

19. A reversible reaction has at a fixed temperature. This value most directly suggests that

20. Selective precipitation is possible when

21. A catalyst is added to a reversible reaction mixture before equilibrium is reached. The most suitable effect is that the catalyst

22. A mixture contains a weak acid , its conjugate base , and a sparingly soluble salt . Adding a strong acid is most likely to

23. When a small amount of strong acid is added to an acidic buffer containing and , the added is mainly consumed by

24. For , when of is taken initially and the total pressure at equilibrium is , the expression for in terms of is

25. Use the arrangement described below: a beaker contains crushed ice and a little liquid water at the melting point. A small amount of heat is supplied slowly while some ice still remains. The most reasonable immediate effect is that

26. The thermodynamic relation connecting standard Gibbs energy change and equilibrium constant is

27. A reversible gaseous reaction has . If at temperature , the correct relation for is

28. In a solution containing , the molar solubility of with is approximately

29. An inert gas is added to a gaseous equilibrium mixture at constant pressure. The volume increases, and the reacting gases are diluted. The shift, if any, is predicted by

30. Equilibrium constants for two reactions are given:


For , the equilibrium constant is

31. A monoprotic strong acid of concentration is assumed to ionize completely. Its is

32. Two equations are related as shown:


The value of is

33. In the equilibrium , adding from a soluble salt will initially

34. A reaction has . Initially, and . If is the amount of consumed, the equation for is

35. A solution is prepared by mixing equal volumes of and . If , the prediction is

36. A concentration-time graph for shows decreasing and increasing. After some time, both curves become horizontal. The horizontal region means that

37. For the equilibrium , , , and at equilibrium. The value of is

38. Equal volumes of and are mixed. If , precipitation will

39. The notation shows that acetic acid

40. A physical equilibrium can be recognized most safely by

41. A statement about physical equilibrium says: “At equilibrium, the measurable property is constant because the forward physical process has stopped.” The better correction is that

42. The relation is used safely only when

43. Two equilibria are given:


For the overall reaction , the equilibrium constant is

44. In applying , a common error is to count all coefficients instead of only gaseous coefficients. For , the correct is

45. A sealed soda bottle contains dissolved under pressure. When the bottle is opened, bubbles appear mainly because

46. A data record gives two equilibrium mixtures for the same reaction at the same temperature.

The best conclusion is that

47. The conjugate acid of is

48. For , at a temperature . The symbolic expression for is

49. For , each of and is taken initially, and . If is the equilibrium concentration of , the equation to solve is

50. The relation means that, among acids at the same temperature,