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Friday, 14 August 2026
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Chemistry Past Questions and Answers

Topic: Separation processes

Jamb Chemistry Questions - Separation processes

Question 16:
Which of the following does NOT contain aluminium as component?
  • A Over-head cables
  • B Duralumin
  • C Container for caustic soda
  • D Container for nitric acid
View Answer & Explanation
Question 17:
The most volatile fraction obtained from fractional distillation of crude petroleum contains?
  • A Butane , propane and kerosene
  • B Butane , propane and petrol
  • C Ethane, methane and benzene
  • D Methane, ethane and propane
View Answer & Explanation
Question 18:
The solubility of Na3AsO4(H2O)12 is 38.9g per 100g H2O. What is the mass percentage of Na3AsO4 in the saturated solution?
(As = 75, Na = 23, O = 16, H = 1)
  • A 87.27%
  • B 38.9%
  • C 19.1%
  • D 13.7%
View Answer & Explanation
Question 19:
A substance S is isomorphous with another substance R. When a tiny crystals of S is added into a supersaturated solution of R?
  • A S dissolves in the solution
  • B Crystals of R are precipitated
  • C There is no observable change
  • D R and S react to generate heat
View Answer & Explanation
Question 20:
Aluminium is extracted commercially from its ore by?
  • A Heating aluminium oxide with coke in a furance
  • B The electrolysis of fused aluminium oxide in cryolite
  • C Treating cryolite with sodium hydroxide solution under prressure
  • D Heating sodium aluminium silicate to a high temperature
View Answer & Explanation