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Sunday, 16 August 2026
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Chemistry Past Questions and Answers

Topic: Water as a solvent

Jamb Chemistry Questions - Water as a solvent

Question 26:
Clothes should be properly rinsed with water after bleaching because
  • A The bleach decolourizes the clothes
  • B Chlorine reacts with fabrics during bleaching
  • C The clothes are sterilized during bleaching
  • D Hydrogen chloride solution is produced during bleaching
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Question 27:
A major process involved in the softening of hard water is the?
  • A Conversation of a soluble calcium salt to its trioxoncarbonate (lV)
  • B Decomposition of calcium rioxocarbonate (lV)
  • C Conversion of an insoluble calcium salts to its trioxocarbonate (lV)
  • D Oxidation of calcium atoms to its ions
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Question 28:
The synthetic detergents are preferred to soap for laundry using hard water because?
  • A Detergents are water soluble while soap is not
  • B The calcium salts of detergents are water soluble
  • C The magnesium salt of soap is soluble in hard water
  • D Soap does not have a hydrocarbon terminal chain
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Question 29:
Potassium tetraoxomanganate (VII) is often added to impure water to?
  • A Reduce organic impurities
  • B Reduce inorganic impurities
  • C Destroy bacteria and algae
  • D Remove permanent hardness
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Question 30:
The solubility product of Cu(IO3)2 is 1.08 * 10-7. Assuming that neither ions react appreciable with water to form H+ and OH-, what is the solubility of this salt?
  • A 2.7 * 10<sup style='font-size: smaller;'>-8</sup> mol dm<sup style='font-size: smaller;'>-3</sup>
  • B 9.0 * 10<sup style='font-size: smaller;'>-8</sup> mol dm<sup style='font-size: smaller;'>-3</sup>
  • C 3.0 * 10<sup style='font-size: smaller;'>-3</sup> mol dm<sup style='font-size: smaller;'>-3</sup>
  • D 9.0 * 10<sup style='font-size: smaller;'>-3</sup> mol dm<sup style='font-size: smaller;'>-3</sup>
View Answer & Explanation