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Wednesday, 22 July 2026
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Chemistry Past Questions and Answers

Jamb 2000 Chemistry Questions

Question 26:
(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 * 10<sub style='font-size: smaller;'>4</sub>C
  • B 4.820 * 10<sub style='font-size: smaller;'>4</sub>C
  • C 9.650 * 10<sub style='font-size: smaller;'>4</sub>C
  • D 48.200 * 10<sub style='font-size: smaller;'>4</sub>C
View Answer & Explanation
Question 27:
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
View Answer & Explanation
Question 28:
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<sup style='font-size: smaller;'>-1</sup>
  • B +300 KJ mol<sup style='font-size: smaller;'>-1</sup>
  • C -300 KJ mol<sup style='font-size: smaller;'>-1</sup>
  • D -3000 KJ mol<sup style='font-size: smaller;'>-1</sup>
View Answer & Explanation
Question 29:
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
View Answer & Explanation
Question 30:
N2(g) + O2(g) ↔ 2NO(g); ΔH = + 180.6 kJ mol-1
In the reaction above, increase in temperature will
  • A Increase the quantity of N<sub style='font-size: smaller;'>2</sub>
  • B Increase in the yield of NO
  • C Decrease the yield of NO
  • D Decrease the quantity of O<sub style='font-size: smaller;'>2</sub>
View Answer & Explanation