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

Question 66:

• JAMB 2006

A difference between chemical and physical change is that in a chemical change

A. Oxygen is consumed
B. Heat is supplied
C. A reversible process oocurs
D. A new substance is formed

Question 67:

• JAMB 2006

The order in which a mixture of sand, ammonium chloride and sodium chloride can be separated is

A. Dissolution → dryness → filtration → evaporation
B. Filtration → sublimation → evaporation → dryness
C. Sublimation → dissolution → filtration → evaporation
D. Dissolution → filtration → sublimation → evaporation

Question 68:

• JAMB 2007

A mixture of petrol and water can be separated through

A. Centrifugation
B. Distillation
C. The use of separating funnel
D. The use of filter paper

Question 69:

• JAMB 2007

Which of the following alkanes has the highest boiling point?

A. Pentane
B. Ethane
C. Propane
D. Methane

Question 70:

• JAMB 2008

Chlorophyll obtained from given leaves of plant can be shown to be composed of more than one coloured component by the technique of

A. Crystallization
B. Hydrolysis
C. Chromatography
D. Sublimation