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Tuesday, 16 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 111:
The IUPAC name for
  • A 2-methylbutanoic acid
  • B 2-methyl-1- hydroxyketone
  • C 2-methyl-1-hydroxy aldehyde
  • D 2-methylpentanoic acid
View Answer & Explanation
Question 112:
Which of the following would support the conclusion that a solid sample is a mixture?
  • A The solid can be ground to a fine powder
  • B The density of the solid is 2.25 g dm<sup style='font-size: smaller;'>3</sup>
  • C The solid has a melting range of 300<sup style='font-size: smaller;'>o</sup>C to 375<sup style='font-size: smaller;'>o</sup>C
  • D The solid absorbs moisture from the atmosphere
View Answer & Explanation
Question 113:
Which of the following would support the conclusion that a solid sample is a mixture?
  • A The solid can be ground to a fine powder
  • B The density of the solid is 2.25 g dm<sup style='font-size: smaller;'>3</sup>
  • C The solid has a melting range of 300<sup style='font-size: smaller;'>o</sup>C to 375<sup style='font-size: smaller;'>o</sup>C
  • D The solid absorbs moisture from the atmosphere
View Answer & Explanation
Question 114:
20.00 cm 3 of a solution containing 0.53 g of anhydrous Na2CO3 in 100 cm3 requires 25.00 cm3 of H2SO4 for complete neutralisation. The concentration of the acid solution in moles per dm is [H =1, C = 12, O = 16, Na =23, S = 32]
  • A 0.02
  • B 0.04
  • C 0.06
  • D 0.08
View Answer & Explanation
Question 115:
The atomic number of caesium is 55 and its atomic mass is 133. The nucleus of caesium atom therefore contains
  • A 78 protons and 55 elections
  • B 55 protons and 78 neutrons
  • C 55 neutrons 78 electrons
  • D 78 protons and 55 neutrons
View Answer & Explanation