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Monday, 17 August 2026
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Chemistry Past Questions and Answers

Topic: Water as a solvent

Jamb Chemistry Questions - Water as a solvent

Question 36:
When dissolved in water, NaOH flakes show
  • A An endothermic change
  • B An exothermic change
  • C A slow reaction
  • D A rapid reaction
View Answer & Explanation
Question 37:
The furring of kettles is caused by the presence in the water of
  • A Calcium tetraoxosulphate (VI)
  • B Calcium hydrogentrioxocarbonate (IV)
  • C Calcium hydroxide
  • D Calcium trioxocarbonate (IV)
View Answer & Explanation
Question 38:
The structural component that makes detergent dissolve more quickly in water than soap is
  • A -SO<sub style='font-size: smaller;'>3</sub>- Na<sup style='font-size: smaller;'>+</sup>
  • B -COO-Na<sup style='font-size: smaller;'>-</sup>
  • C -SO<sub style='font-size: smaller;'>4</sub>- Na<sup style='font-size: smaller;'>+</sup>
  • D -COO-K<sup style='font-size: smaller;'>+</sup>
View Answer & Explanation
Question 39:
When 10g of sodium hydroxide is dissolved in 1000cm3 of water, the sodium formed is approximately
[Na = 23, H = 1, O = 16]
  • A 0.01 mol dm<sup style='font-size: smaller;'>-3</sup>
  • B 0.10 mol dm<sup style='font-size: smaller;'>-3</sup>
  • C 0.25 mol dm<sup style='font-size: smaller;'>-3</sup>
  • D 0.50 mol dm<sup style='font-size: smaller;'>-3</sup>
View Answer & Explanation
Question 40:
Hardness of water is caused by the presence of ions of
  • A Magnesium and silver
  • B Cacium and magnesium
  • C Sodium and potassium
  • D Calcium and sodium
View Answer & Explanation