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Sunday, 14 June 2026
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Chemistry Past Questions and Answers

Waec Chemistry Questions

Question 1416:
When water was added to a white anhydrous substance X, the colour changed to blue. X is
  • A \(CuSO_{4}\)
  • B \(FeSO_{4}\)
  • C \(Na_{2}SO_{4}\)
  • D \(PbSO_{4}\)
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Question 1417:
Solubility curve can be used in the determination of the
  • A Amount of crystals formed
  • B Amount of solvent that can be recovered
  • C Amount of solid drugs in a given solution
  • D Temperature of the solution
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Question 1418:
If 0.2g of a salt is required to saturate 200\(cm^{3}\) of water at room temperature, what is the solubility of the salt?
  • A 0.2\(gdm^{-3}\)
  • B 1.0\(gdm^{-3}\)
  • C 2.0\(gdm^{-3}\)
  • D 5.0\(gdm^{-3}\)
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Question 1419:
The property of a chemical reaction that is affected by the presence of a catalyst is
  • A Activation energy
  • B Free energy
  • C Equilibrium position
  • D Enthalpy change
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Question 1420:
Soluble salts can be prepared by the following methods except
  • A Neutralization
  • B Reaction of an acid with trioxocarbonate(IV) salt
  • C Double decomposition
  • D Reaction of an acid with electropositive metals
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