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Thursday, 11 June 2026
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Chemistry Past Questions and Answers

Jamb 2002 Chemistry Questions

Question 1:
A compound contains 31.91% potassium, 28.93% chlorine and the rest oxygen. What is the chemical formula of the compound?
[K = 39, Cl = 35.5, O = 16]
  • A KClO<sub style='font-size: smaller;'>4</sub>
  • B KClO
  • C KClO<sub style='font-size: smaller;'>2</sub>
  • D KClO<sub style='font-size: smaller;'>3</sub>
View Answer & Explanation
Question 2:
A compound contains 31.91% potassium, 28.93% chlorine and the rest oxygen. What is the chemical formula of the compound?
[K = 39, Cl = 35.5, O = 16]
  • A KClO<sub style='font-size: smaller;'>4</sub>
  • B KClO
  • C KClO<sub style='font-size: smaller;'>2</sub>
  • D KClO<sub style='font-size: smaller;'>3</sub>
View Answer & Explanation
Question 3:
The formula CH2 for ethanoic acid is regarded as its
  • A Molecular formula
  • B General formula
  • C Empirical formula
  • D Structural formula
View Answer & Explanation
Question 4:
A little quantity of trichloromethane (b.pt 60,oC) was added to a large quantity of ethanol (b.pt 78,oC). The most probable boiling point of the resultant mixture is from
  • A 69 <sup style='font-size: smaller;'>o</sup>C - 70 <sup style='font-size: smaller;'>o</sup>C
  • B 70 <sup style='font-size: smaller;'>o</sup>C – 74 <sup style='font-size: smaller;'>o</sup>C
  • C 82 <sup style='font-size: smaller;'>o</sup>C – 84 <sup style='font-size: smaller;'>o</sup>C
  • D 60 <sup style='font-size: smaller;'>o</sup>C – 78 <sup style='font-size: smaller;'>o</sup>C
View Answer & Explanation
Question 5:
The chromatography separation of ink is based on the ability of the components to
  • A React with solvent
  • B React with each other
  • C Dissolve in each other in the column
  • D Move at different speeds in the column
View Answer & Explanation