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

Question 26:

• JAMB 1986

The movement of liquid molecules from the surface of the liquid to the gaseous phase above it is known as?

A. Brownian movement
B. Condensation
C. Evaporation
D. Liquefaction

Question 27:

• JAMB 1988

In the experiment above, ammonium chloride crystals deposit on the walls of the tube is as a result of

A. Evaporation
B. Recrystallization
C. Sublimation
D. Fractional precipitation

Question 28:

• JAMB 1989

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 dm³
C. The solid has a melting range of 300^oC to 375^oC
D. The solid absorbs moisture from the atmosphere

Question 29:

• JAMB 1989

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 dm³
C. The solid has a melting range of 300^oC to 375^oC
D. The solid absorbs moisture from the atmosphere

Question 30:

• JAMB 1989

Bleaching powder, CaOCI₂, H₂O, deteriorates on exposure to air because

A. It loses its water of crystallization
B. Atmospheric nitrogen displaces chlorine from it
C. Carbon (IV) oxide of the atmosphere displaceschlorine from it
D. Bleaching agents should be stored in solution