Chemical Equilibrium Test Online MCQs

1. An increase in reaction velocity is due to:

2. One mole of A and one of mole B are mixed in a vessel to produce C and (d). At the equilibrium, 0.2 mole of B are left unreacted. The value of the equilibrium constant for the reaction will be:

3. For an equilibrium reaction, the rate constant for the forward reaction is 2.38x10-⁴. The equilibrium constant for the reaction is:

4. For the reaction, 2Hl ⇌ H₂ + I₂, the equilibrium constant K at 490 ͦC is0.022. The equilibrium constant of the reverse reaction will be:

5. The decomposition of N₂O₄ to NO₂ is carried at 280 k in chloroform. When the equilibrium has been established, 0.2mole of N₂O₄ 2x10-³ mole of NO₂ are present in a two-litre solution. The equilibrium constant for the reaction N₂O₄ ⇌ 2NO₂ is:

6. When pressure is applied to the equilibrium system. Ice(s) ⇌ H₂O(l), which of the following will happen?

7. Which of the following is the correct statement for the manufacture of ammonia by Haber’s process?

8. 0.2 mole of an inert gas were added to the system 2Hl(g) ⇌ H₂(g) + I₂(g) at equilibrium. The dissociation of HI will:

9. The equilibrium constant for the reaction, N₂(g) + 3H₂(g) ⇌ 2NH₃(g) is K. The value of the constant for the reaction NH₃(g) ⇌ ½ N₂(g) + 2/3H₂(g) will be:

10. One gm mole of CH₃COOH were made to react with one gm mole of C₂H₅OH till the equilibrium was established. The equilibrium mixture was found to contain 0.333 gm mole of unused acid. The equilibrium constant for the reaction is:

11. Given the reaction:
2A (gas) + B(gas) ⇌ C (gas) = 100 kJ Which combination of pressure and temperature would give the highest yield of C at equilibrium?

12. At constant pressure, upon the addition of helium at the equilibrium point in the reaction, PCl₅ (g) ⇌ PCl₃(g) + Cl₂(g), the degree of dissociation of:

13. A cylinder provided with a piston has some PCl₅ in equilibrium with and Cl₂ formed by the dissociation of PCl₅. If the system is compressed, then indicate the correct statement:

14. According to Law of Mass action, the rate of reaction is directly proportional to:

15. In the reaction PCl₅ (g) ⇌ PCl₃ (g) + Cl₂(g) at 760K, 4.0 moles of PCl₅ are taken in a 2-liter flask to
contain 0.80 mole of Cl₂. The value of equilibrium constant will be:

16. The decomposition of PCl₅ at 323 K proceeds as PCl₅ (s) ⇌ PCl₃  (g) + Cl₂(g). If the degree is dissociation of PCl₅ be α and the equilibrium pressure be P, then the partial pressure due to chlorine will be:

17. . In the equilibrium,
H₃PO₄ + H₂O ⇌ H₂PO-₄ + H₂O⁺
The equilibrium constant is most likely to be changed by:

18. For the reversible reaction:
N₂(g) + 3H₂ (g) ⇌ 2NH₃ (g) ΔH is -93.7 kJ. The equilibrium will shift in the forward direction, if conc. Of

19. A relatively fast reaction is characterized by a:

20. When pressure is applied to equilibrium system of ice ⇌ water, which of the following phenomenon will occur?