Jamb Chemistry Past Questions and Answers

Question 701:

• JAMB 1991

1.1 g of CaCI2 dissolved in 50 cm3 of water caused a rise in temperature of3.4°C. The heat of reaction, ∆H for CaCI2 in kj per mole is?
(Ca = 40, CI = 35.5, specific heat of water is 4.18 jk-1

A. -71.1
B. -4.18
C. +71.1
D. +111.0

Question 702:

• JAMB 1991

NO_(g) + CO_(g) ↔ (1)/(2)N_2(g) + CO_2(g) ∆H = -89.3 kj.
What conditions would favour maximum conversion of nitrogen (II) oxide and carbon (II) oxide in the reaction above?

A. Low temperature and high pressure
B. High temperature and low pressure
C. High temperature and high pressure
D. Low temperature and low pressure

Question 703:

• 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 704:

• JAMB 1991

Which of the following gases will rekindle a brightly glowing splint?

A. NO₂
B. NO
C. N₂O
D. CI₂

Question 705:

• JAMB 1991

Which of the following salts can be melted without decomposition?

A. Na₂CO₃
B. CaCO₃
C. MgCO₃
D. ZnCO₃