Chemistry 2000 Jamb Past Questions and Answers

Question 26 :

• JAMB 2000

(1/2)Zn²⁺_(aq) + e^- → (1/2) Zn_(s)
In the reaction above, calculate the quantity of electricity required to discharge zinc.
[F = 96 500 C mol^-1]

A. 0.965 * 10₄C
B. 4.820 * 10₄C
C. 9.650 * 10₄C
D. 48.200 * 10₄C

Question 27 :

• JAMB 2000

Given that M is the mass of substance deposited in an electrolysis and Q the quantity of electricity consumed, then Faraday's law can be written as

A. M = Z/Q
B. M = Q/Z
C. M = Z/2Q
D. M = QZ

Question 28 :

• JAMB 2000

0.46g of ethanol when burned raised the temperature of 50g of water by 14.3K. Calculate the heat of combustion of ethanol.
[C = 12, O = 16, H = 1, Specific heat capacity of water = 4.2 jg^-1K^-1]

A. +3000 KJ mol^-1
B. +300 KJ mol^-1
C. -300 KJ mol^-1
D. -3000 KJ mol^-1

Question 29 :

• JAMB 2000

Powdered marble reacts faster with hydrochloric acid solution than the granular form because the powdered form has

A. More molecules
B. More atoms
C. Larger surface area
D. Relatively large mass

Question 30 :

• JAMB 2000

N_2(g) + O_2(g) ↔ 2NO_(g); ΔH = + 180.6 kJ mol^-1
In the reaction above, increase in temperature will

A. Increase the quantity of N₂
B. Increase in the yield of NO
C. Decrease the yield of NO
D. Decrease the quantity of O₂