Search SchoolNGR

Saturday, 13 June 2026
Register . Login

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 6:
By means of filtration, one component can be obtained pure from an aqueous mixture of sodium chloride and
  • A Potassium nitrate
  • B Sand
  • C Lead nitrate
  • D Sugar (glucose)
  • E Starch
View Answer & Explanation
Question 7:
A gas jar was inverted over burning yellow phosphorus floating over water in a beaker. After burning, the water level was found to rise in the gas jar. The water level rises because
  • A Pressure inside the gas jar is greater than pressure outside it
  • B The air in the gas jar had been used up by burning
  • C Oxygen in the gas jar had been used up by burning
  • D Nitrogen in the gas jar had been used up by burning
  • E The temperature in the jar had risen considerably
View Answer & Explanation
Question 8:
Which of the following substances would you see as an indicator in the titration of sodium carbonate solution against hydrochloric acid (complete neutralisation)?
  • A Litmus paper
  • B Phenolphthalein
  • C Methyl orange
  • D Universal indicator
  • E None of these
View Answer & Explanation
Question 9:
200cm3 each of 0.1M solutions of lead (II) trioxonitrate (V) and hydrochloric acid were mixed. Assuming that lead (II) chloride is completely insoluble, calculate the mass of lead (II) chloride that will be precipitated.
[Pb = 207, Cl= 35.5, N = 14, O = 16]
  • A 2.78g
  • B 5.56g
  • C 8.34g
  • D 11.12g
  • E 16.45g
View Answer & Explanation
Question 10:
How many alkoxyalkanes can be obtained from the molecular formula C4H10O?
  • A 4
  • B 2
  • C 1
  • D 3
View Answer & Explanation