CBSE Class 11 Chemistry Chemical Equilibrium MCQs Set A

CBSE Class 11 Chemistry Chemical Equilibrium MCQs Set A. CBSE and NCERT students can refer to the attached file. All educational material on the website has been prepared by the best teachers having more than 20 years of teaching experience in various schools. The study material available on our website for all CBSE classes and subjects have been prepared by teachers from all over the country. All study material has been carefully designed keeping into mind the latest CBSE examination trends.  

I. MCQ - Choose Appropriate Alternative

1. At equilibrium the rate of forward reaction and the rate of reverse reaction are __________. (Equal, Changing, Different)

2. Such reactions, which proceed to forward direction only and are completed after sometime are called __________ reaction. (Irreversible, Reversible, Molecular)

3. Such reactions, which proceed to both the direction and are never completed, are called __________ reaction. (Irreversible, Reversible, Molecular)

4. The rate of chemical reaction is directly proportional to the product of the molar concentration of __________. (Reactants, Products, Both reactants and products)

5. “If a system in equilibrium is subjected to a stress, the equilibrium shifts in a direction to minimize or undo the effect of this stress. This principle is known as __________. (Le-Chatelier’s Principle, Gay Lussac’s Principle, Avogadro’s Principle)

6. A very large value of K_c indicates that reactants are __________. (very stable, unstable, moderately stable)

7. A very low value of K_c indicates that reactants are __________. (very stable, very unstable, moderately stable)

8. The equilibrium in which reactants are products are in single phase is called __________. (Homogenous Equilibrium, Heterogenous Equilibrium, Dynamic Equilibrium)

9. The equilibrium in which reactants and products are in more than one phases are called __________. (Homogenious Equilibrium, Heterogenious Equilibrium, Dynamic Equilibrium)

10. Chemical Equilibrium is __________ equilibrium. (Dunamic, Static, Heterogeneous)

11. In exothermic reaction, lowering of temperature will shift the equilibrium to __________. (right, left, equally on both the direction)

12. In endothermic reaction, lowering of temperature will shift the equilibrium to __________. (right, left, equally on both the direction)

13. A catalyst __________ the energy of activation. (increases, decreases, has no effect on)

14. At equilibrium point __________. (forward reaction is increased, backward reaction is increased, forward and backward reactions become equal)

15. NH₃ is prepared by the reaction N₂ + 3H₂ → 2NH₃ ; ΔH = -21.9 Kcal. The maximum yield of NH3 is obtained __________. (At low temperature and high pressure, at high temperature and low pressure, at high temperature and high pressure)

16. When a high pressure is applied to the following reversible process: N₂ + O₂ →2NO The equilibrium will __________ (shift to the forward direction, shift to the backward direction, not change)

17. The value of Kc __________ upon the initial concentration of the reaction. (depends, partially depends, does not depend)

18. While writing the Kc expression, the concentration of __________ are taken in the numerator.

19. Solubility product constant is denoted by __________. (Kc, Ks_p, Kr)

20. “The degree of ionization of an electrolyte is suppressed by the addition of another electrolyte containing a common ion.” This phenomenon is called __________. (Solubility Product, Common Ion Effect, Le-Chatelier’s Principle)

II. Fill in the Blanks

1. The reactions, which proceed in both the directions, are called __________ reactions.

2. The reactions, which proceed to one direction only, are called __________ reactions.

3. Reversible reactions are __________ completed.

4. Irreversible reactions are __________ after some time.

5. A reversible reaction is said to be in __________ when the rate of forward reaction becomes equal to the rate of backward reaction.

6. The concentrations of reactants and products are __________ at equilibrium point.

7. The value of Kc depends upon the __________ of the reactants.

8. A increase of the value of Kc tends to move the reaction to the __________ direction.

9. A decrease of the value of Kc tends to move the reaction to the __________ direction.

10. An increase in the concentration of the reactants will move the reaction to the __________ direction.

11. A decrease in the concentration of the reactants will move the reaction to the __________ direction.

12. Equilibrium constant is denoted by __________.

13. When the equilibrium constant value is very __________, we can conclude that the forward reaction is almost completed.

14. When equilibrium constant value is very __________ we can conclude that forward reaction will occur to very little extent.

15. According to __________ principle, if system in equilibrium is subjected to a stress, the equilibrium shifts in a direction to minimize or undo the effect of the stress.

16. In exothermic reaction, the __________ of temperature favour the forward rate of reaction.

17. In endothermic reactions, the __________ of temperature favour the forward rate of reaction.

18. A __________ is a substance which effects the rate of reaction but remains unaltered at the end of the reaction.

19. A catalyst increases the velocity of the reaction by decreasing the __________.

20. The suppression of degree of ionization of a sparingly soluble weak electrolyte by the addition of a strong electrolyte containing an ion in common is called __________.

21. __________ is purified in industries by Common Ion Effect.

22. A reaction moves to the left when the concentrations of the products are __________.

23. A reaction moves to the right when the concentrations of the products are __________.

24. Increase in pressure will move the reaction in the direction of __________ volume.

25. Decrease in pressure will move the reaction in the direction of __________ volume.

26. An increase of temperature favours the formation of products in case of __________ reaction.

27. A decrease of temperature fovours the formation of products in case of __________ reaction.

28. Heating moves an endothermic reaction to the __________.

29. Cooling move an exothermic reaction to the __________.

30. The product of ionic concentration in a saturated solution is called __________ constant.

31. When HCl is added to NaCl, the concentration of __________ ion is increased.

32. Chemical reaction involving the substances in more than one phases are called __________.

33. The formation of NH₃ is exothermic process hence __________ temperature will favour the formation of NH₃.

34. The formation of NO from N₂ and O₂ is endothermic process hence __________ temperature will favour the formation of NO.

35. Chemical Equilibrium is __________ equilibrium.

36. Molar concentration is also called __________.

37. The rate at which a substance takes part in a chemical reaction depends upon its __________.

38. __________ principle is applied to all reversible reaction.

39. A common ion __________ the solubility of the salt.

40. Number of moles present per dm3 of a substance is called __________.