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Monday, 15 June 2026
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Chemistry Past Questions and Answers

Topic: Separation of mixtures and purification of chemical substances

Jamb Chemistry Questions - Separation of mixtures and purification of chemical substances

Question 31:
In an attempt to remove sugar from a breaker containing a quantity of sand and sugar, 2 M ammonium chloride solution was accidentally added instead of water. Which of the following method could be used to remove the ammonium chloride from the mixture?
  • A Fractional distillation
  • B Crystallization
  • C Filtration followed by evaporation
  • D Evaporation followed by sublimation
  • E Filtration followed by sublimation
View Answer & Explanation
Question 32:
In an attempt to remove sugar from a breaker containing a quantity of sand and sugar, 2 M ammonium chloride solution was accidentally added instead of water. Which of the following method could be used to remove the ammonium chloride from the mixture?
  • A Fractional distillation
  • B Crystallization
  • C Filtration followed by evaporation
  • D Evaporation followed by sublimation
  • E Filtration followed by sublimation
View Answer & Explanation
Question 33:
A solution X on mixing with AgNO3 solution, gives a white precipitate solution in NH3. A Solution Y, when added to X, also gives a white precipiate which is soluble on boiling. Solution Y contains?
  • A Ag<sup style='font-size: smaller;'>+</sup>ion
  • B Pb<sup style='font-size: smaller;'>2+</sup>ion
  • C Pb<sup style='font-size: smaller;'>4+</sup>ion
  • D Zn<sup style='font-size: smaller;'>2+</sup>ion
  • E Al<sup style='font-size: smaller;'>3+</sup>ion
View Answer & Explanation
Question 34:
Which of the following statements is true?
  • A Metals conduct electricity while non-metals do not
  • B Metals have high density, non-metals have low density
  • C Metals form basic oxides, non-metals form acidic oxides
  • D In the electro chemical series, metals are above hydrogen while non-metals are below hydrogen
  • E Metals lose elections while non-metals gain electron during normal reactions
View Answer & Explanation
Question 35:
Which ONE of the following statements is true?
  • A All alkali metals salts dissolves with dissociation in water
  • B Most ionic substances are easily vaporized
  • C Ionic substances exist only as liquid
  • D Non-ionic substances are good electrolytes
  • E Nitrogen exists in a trivalent state in ammonium salts
View Answer & Explanation