Chemical combination - Jamb Chemistry Past Questions and Answers

Question 56:

• JAMB 1991

A sample of a gas exerts a pressure of 8.2 atm when confined in a 2.93 dm³ container at 20°C. The number of moles of gas in the sample is?
(R = 0.082 litre atm / deg mole)

A. 1.00
B. 2.00
C. 3.00
D. 4.00

Question 57:

• 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 58:

• JAMB 1991

How many grams of bromine will be required to completely react with 10 g of propyne?
(C = 12, H = 1, Br = 80)

A. 20 g
B. 40 g
C. 60 g
D. 80 g

Question 59:

• JAMB 1992

How many moles of (H+) are there in 1 dm³ of 0.5 M solution of H₂SO₄?

A. 2.0 moles
B. 1.0 moles
C. 0.5 mole
D. 0.25 mole

Question 60:

• JAMB 1992

A given mass of gas occupies 2 dm² at 300k. At what temperature will its volume be doubled keeping the pressure constant?

A. 400k
B. 480k
C. 550k
D. 600k