Class 11 Chemistry — Chapter 7: Equilibrium Online Test

1. In qualitative inorganic analysis, group IV cations are precipitated in ammoniacal medium because

2. If the solubility of (AgCl) is , the value is

3. When in a basic buffer, the pH equals

4. The hydrolysis constant is defined as

5. The pH of a (0.1,M) solution of is

6. The (pH) of a (0.2,M) solution is

7. The pH of a solution is defined as

8. According to Ostwald’s law, the degree of ionization is related to

9. For a weak base solution where , the hydroxide ion concentration is

10. The ionization constant of an acid is a measure of its

11. In the reaction , the Brønsted–Lowry base is

12. When the concentration of a reactant is increased in a system at equilibrium, the equilibrium

13. The main difference between and is that

14. For a general reaction , the expression for is

15. For at fixed (T), raising the external pressure of an inert gas at constant volume changes the extent of decomposition

16. For at a temperature where , starting with stoichiometric at 1 atm, the equilibrium extent toward is

17. The reaction has at 500 K. If initially is high and are low, the reaction will

18. For the equilibrium , the equilibrium constant expression is

19. For a heterogeneous equilibrium such as , the equilibrium constant is expressed as:

20. For at , . If initially and , the reaction will:

1. For a reaction , the direction of the reaction can be predicted by comparing

2. For a neutral solution at 25°C,

3. The base ionization constant expresses

4. For an endothermic reaction, decreasing temperature causes

5. For the reaction , the units of are

6. The units of for are

7. The degree of ionization of a weak acid is related to its concentration (( C )) as

8. Consider with at 298 K. Starting from , the expected equilibrium is

9. According to the Brønsted–Lowry concept, a base is a substance that

10. For a weak acid solution, if concentration decreases 100 times, the degree of ionization increases approximately by a factor of

11. The (pH) of a salt solution formed by a weak acid and strong base can be expressed as

12. A sealed flask contains at temperature (T). Doubling the mass of while keeping (T) fixed will

13. At the melting point of a pure solid in a closed system, solid–liquid equilibrium is characterized by:

14. The reaction is a homogeneous equilibrium because

15. Henry’s law for a sparingly soluble gas in a liquid is correctly written as:

16. The conjugate base of a strong acid is always

17. According to Arrhenius, a base is a substance that

18. In at constant temperature, the equilibrium constant is numerically equal to

19. For , if initial and , the equilibrium is

20. For with and initial , the equilibrium fraction of (A) converted is

21. The main function of a buffer in biological systems is to

22. For the reaction with and initial , the equilibrium is

23. Why does a chemical system at equilibrium appear static to the observer?

24. For at , , and rate constants , . Which calculation indicates dynamic equilibrium?

25. Which of the following statements is true for homogeneous equilibrium systems?

26. For , the correct expression for is:

27. When the concentration of a weak acid is decreased to one-fourth, the degree of ionization

28. For with starting from , , the approximate equilibrium is

29. Which of the following is not a weak electrolyte?

30. The Arrhenius concept is limited to

1. For , with and initial , equilibrium is

2. The expression for of is

3. For the reaction with and initial , equilibrium is approximately

4. If for a given reaction mixture, the reaction will

5. The equilibrium constant for a gaseous reaction increases with temperature if the reaction is:

6. Strong bases are those that

7. The solubility product differs from the ionic product in that

8. When the concentration of products is increased at equilibrium, the system

9. The reversible decomposition of calcium carbonate is an example of:

10. The pH of a (0.05,M) (KOH) solution is

11. Which is a correct necessary condition embedded in the definition of chemical equilibrium for a gas-phase reaction?

12. The pair is an example of

13. Which statement about buffers is true?

14. Decreasing pressure on a gaseous equilibrium mixture causes the equilibrium to shift

15. The pH of an acidic buffer can be calculated using

16. The reaction is a homogeneous equilibrium because

17. For the reaction with and initial , the equilibrium concentration of (HI) is

18. Which of the following is a correct example of physical equilibrium?

19. If an inert gas is added at constant pressure, the equilibrium shifts

20. For , if and initial concentrations of all species are , then equilibrium concentrations will

21. When pressure on a gaseous equilibrium is increased, the system shifts

22. For a weak acid solution of concentration (C), the hydrogen ion concentration is approximately

23. In the reaction , the Brønsted–Lowry base is

24. According to the Brønsted–Lowry concept, an acid is a substance that

25. For a system with , , the sign of is

26. For , if initial concentrations of all species are and , the equilibrium will be

27. Which of the following is the best Lewis base toward ?

28. Which statement best describes the “dynamic” nature of equilibrium?

29. The strength of an acid is determined by the magnitude of its

30. The Haber process is exothermic. Which change increases the equilibrium yield of ?

31. If the dielectric constant of a medium increases, the force of attraction between ions

32. For an endothermic reaction, increasing temperature shifts equilibrium

33. A closed flask containing water at shows constant vapour pressure. Which measurement provides direct evidence that liquid–vapour equilibrium is dynamic?

34. The relation between force of attraction ( F ) and dielectric constant ( D ) is

35. The expression for the hydrolysis constant of a salt of a weak acid and a strong base is

36. The dielectric constant of water at 25°C is approximately

37. For the heterogeneous equilibrium , the mass-action law gives:

38. The relation is valid only when

39. According to the Brønsted–Lowry concept, a base is a substance that

40. If a solution has , what is its ( pH ) value?

41. Temperature generally affects degree of ionization of weak acids/bases by

42. In the Contact process, the catalyst used to oxidize is

43. In the reaction , if and , the reaction will

44. The ionization constant of acetic acid is . This indicates it is

45. For the reaction with and initial concentrations , , the equilibrium concentration of (B) is

46. The coexistence of macroscopic constancy and microscopic reversibility means that:

47. When ( Q < K ) for a reaction, the system will

48. The pH of a basic buffer is given by

49. Which of the following best expresses the definition of physical equilibrium?

50. In the reaction , the conjugate base of is