Chemical equilibrium - Jamb Chemistry Past Questions and Answers

Question 6:

• JAMB 1988

Which property of a reversible reaction is affected by a catalyst?

A. Heat content (enthalphy)
B. Energy of activation
C. Free energy change
D. Equilibrium position

Question 7:

• JAMB 1989

The above graph shows a typical heating curve from the solid phase through the liquid phase to the gaseous phase of a substance. Which part of the curve shows solid and liquid in equilibrium?

A. T
B. U
C. X
D. Y

Question 8:

• JAMB 1990

In the reaction:
2Hl_(g) ↔ H_2(g) + l_2(g)' ΔH = 10 kj;
The concentration of iodine in the equilibrium mixture can be increased by?

A. Raising the pressure
B. Raising the temperature
C. Adding a catalyst
D. Lowering the pressure

Question 9:

• JAMB 1991

Which of the following equilibria is unaffected by a pressure change?

A. 2NaCI(s) ↔ 2Na _(I) + CI_2(g)
B. H _2(g) + I_2(g) ↔ 2HI_(g)
C. 2O_3(g) ↔ 3O_2(g)
D. 2NO_2(g) ↔ N₂O_4(g)

Question 10:

• JAMB 1992

In what way is equilibrium constant for the forward reaction related to that of the reversed reaction?

A. The additional of the two is expected to be one
B. The product of the two is expected to be one
C. The two equilibrium constants are identical
D. The product of the two is always greater than one