Chemical Equilibrium Test Online MCQs

1. 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:

2. 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:

3. 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

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. 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:

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

9. A relatively fast reaction is characterized by a:

10. An increase in reaction velocity is due to:

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

12. 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:

13. 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:

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

15. 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:

16. 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?

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

18. 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:

19. 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:

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