Jamb Chemistry 2003 Past Questions and Answers

Question 26:

• JAMB 2003

When at equilibrium, which of the reactions below will shift to the right if the pressure is increased and the temperature is kept constant?

A. 2SO_3(g) ↔ 2SO_2(g) + O_2(g)
B. 2CO_2(g) ↔ 2CO_(g) + O_2(g)
C. 2H_2(g) + O_2(g) ↔ 2H₂O_(g)
D. 2NO_(g) ↔ N_2(g) + O_2(g)

Question 27:

• JAMB 2003

In the electrolysis of a concentrated solution of sodium chloride using electrodes, which of the following ions are discharged at the cathode and anode respectively?

A. Na⁺ and Cl^-
B. Na⁺ and OH^-
C. H⁺ and OH^-
D. H⁺ and Cl^-

Question 28:

• JAMB 2003

CO_(g) + H₂O_(g) → CO_2(g) + H_2(g)
From the reaction above, calculate the standard enthalpies of formation of CO_2(g), H₂O_(g) and CO_(g) in kJ mol^-1 are -394, -242, and -110 respectively.

A. -262 kJ mol^-1
B. -42 kJ mol^-1
C. +42 kJ mol^-1
D. +262 kJ mol^-1

Question 29:

• JAMB 2003

When sugar is dissolved in tea, the reaction is always accomplished by

A. Positive change
B. Negative entropy change
C. No entropy change
D. A minimum entropy change

Question 30:

• JAMB 2003

Which of the following is an electrolyte?

A. Alcohol
B. Sodium acetate solution
C. Solid potassium hydroxide
D. Mercury