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Friday, 22 May 2026
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Chemistry Past Questions and Answers

Jamb 1991 Chemistry Questions

Question 21:
How many structural isomers can be written for the alkyl bromide, C4H9Br?
  • A 3
  • B 4
  • C 6
  • D 8
View Answer & Explanation
Question 22:
What volume of CO2 at s.t.p would be obtained by reacting trioxocarbonate (IV) with excess acid?
(G.M.V at s.t.p = 22.4 dm3)
  • A 2.240 cm <sup style='font-size: smaller;'>3</sup>
  • B 22.40 cm <sup style='font-size: smaller;'>3</sup>
  • C 224.0 cm <sup style='font-size: smaller;'>3</sup>
  • D 2240 cm <sup style='font-size: smaller;'>3</sup>
View Answer & Explanation
Question 23:
If a current of 1.5 A is passed for 4.00 hours through a molten tin salt and 13.3g of tin is deposited, what is the oxidation state of the metal in the salt?
(Sn = 118.7, F = 96500 C mol-1)
  • A 1
  • B 2
  • C 3
  • D 4
View Answer & Explanation
Question 24:
Which of the following equimolar solutions, Na2CO3 Na2 SO4CI FeCI3 CH3COONa,
have pH greater than 7?
  • A FeCI <sub style='font-size: smaller;'>3</sub> and NH <sub style='font-size: smaller;'>4</sub>CI
  • B Na<sub style='font-size: smaller;'>2</sub>CO<sub style='font-size: smaller;'>3</sub>, CH<sub style='font-size: smaller;'>3</sub>COONa and Na,Na<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub>
  • C Na<sub style='font-size: smaller;'>2</sub>CO<sub style='font-size: smaller;'>3</sub> and CH<sub style='font-size: smaller;'>3</sub>COONa
  • D FeCI<sub style='font-size: smaller;'>3</sub>, CH<sub style='font-size: smaller;'>3</sub>COONa and NH<sub style='font-size: smaller;'>4</sub>CI
View Answer & Explanation
Question 25:
MnO-4 + 8H+ + ne → Mn++ + 4H2O. Which is the value of n in the reaction above?
  • A 2
  • B 3
  • C 4
  • D 5
View Answer & Explanation