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

Question 121:

• JAMB 2019

Which of the following sets of operation will completely separate a mixture of sodium chloride, sand and iodine?

A. Addition of water, filtration, evaporation to dryness and sublimation
B. Filtration, evaporation to dryness, addition of water and sublimation
C. Sublimation, filtration, evaporation and addition of water
D. Sublimation, addition of water, filtration and evaporation to dryness

Question 122:

• JAMB 2020

Which of the following can be obtained by fractional distillation?

A. Nitrogen from liquid air
B. Sodium Chloride from sea water
C. Iodine from solution of Iodine in carbon tetrachloride
D. Sulphur from the solution of sulphur in carbon disulphide

Question 123:

• JAMB 2020

What process would coal undergo to give coal gas, coal tar, ammoniacal liquor and coke?

A. Steam distillation
B. Destructive distillation
C. Liquefication
D. Hydrolysis

Question 124:

• JAMB 2020

Which of the following substances is a mixture?

A. Granulated sugar
B. Seawater
C. Sodium chloride
D. Iron filling

Question 125:

• JAMB 2020

If the quantity of oxygen occupying 2.76L container at a pressure of 0.825 atm and 300k is reduced by one-half, what is the pressure exerted by the remaining gas?

A. 1.650atm
B. 0.825atm
C. 0.413atm
D. 0.275atm