Air - Jamb Chemistry Past Questions and Answers

Question 1:

• JAMB 2019

Which of the following will have its mass increased when heated in air?

A. Helium
B. Magnesium
C. Copper pyrites
D. Glass

Question 2:

• JAMB 2019

Nitrogen obtained from the liquefaction of air has a higher density than that obtained from nitrogen containing compounds because the former contains

A. Water vapour
B. Oxygen
C. Carbon (IV) oxide
D. Rare gases

Question 3:

• JAMB 1978

When air which contains the gases Oxygen, nitrogen, carbondioxide, water vapour and the rare gases, is passed through alkaline pyrogallol and then over quicklime, the only gases left are;

A. Nitrogen and carbondioxide
B. The rare gases
C. Nitrogen and oxygen
D. Nitrogen and the rare gases
E. Nitrogen, carbondioxide and the rare gases

Question 4:

• JAMB 1978

You are provided with five gas jars containing SO₂, CO₂, H₂, CO and NO respectively. Select a test from A to E which will identify ANY ONE of the gases completely

A. Pass each gas into lime water
B. Pass each gas into water and test with litmus paper
C. Pass each gas into concentrated sulphuric acid
D. Expose each gas to atmospheric air
E. Expose each gas to fumes of hydrogen chloride

Question 5:

• JAMB 1979

When carbondioxide is bubbled into limewater a white precipitate is formed. If the passage of the gas is continued, the precipitate disappears. The reason for this is

A. Calcium carbonate is formed which on reaction dissolves
B. Calcium hydrogen carbonate is precipitated and then dissolves
C. Calcium carbonate is formed which on reaction with further carbondioxide forms solube calcium hydrogen carbonate
D. Concentration of the solution has occurred with the deposition of calcium hydroxide
E. The solution has become saturated and solid carbondioxide has been deposited