Jamb Chemistry Past Questions and Answers

Question 126:

• JAMB 1979

If chlorine gas is bubbled into water and then this yellowish-green coloured solution is exposed to bright sunlight for a while

A. The solution will give out chlorine gas and hydrogen chloried gas
B. The solution will produce chlorine gas and oxygen
C. The solution will give out solution will producing hypochloric acid
D. The solution is decomposed giving out oxygen, hydrogen and chlorine
E. The solution will give out oxygen gas leaving behind aqueous hydrochloric acid

Question 127:

• JAMB 1979

12 g of solid protassium chlorate (KCIO) were added to 40 g of water and heated to dissolve all the solid. As the solution cools, crystals of potassium chlorate at 66 ^oC. The solubility of potassium chlorate at 66 ^oC is therefore

A. 66
B. 33
C. 10
D. 20
E. 30

Question 128:

• JAMB 1979

In the electrolysis of dilute sulphuric acid using platinum electrodes, the products obtained at the anode and cathode are:
Anode Cathode

A. Sulphur hydrogen
B. Hydrogen oxygen
C. Oxygen Hydrogen
D. Hydrogen sulphate ions
E. Sulphur oxygen

Question 129:

• JAMB 1979

The empirical formula of an oxide of nitrogen containing 30.4 per cent of nitrogen is (N=14.0,O=16.0)

A. N₂O₂
B. NO
C. NO₂
D. N₂O
E. N₂O₃

Question 130:

• JAMB 1979

When a piece of charcoal enclosed in a cylinder containing air is ignited

A. The toatl volume of air is increased
B. The relative amount of oxygen present is increased
C. The relative amount of nitrogen present is decreased
D. The relative amount of carbondioxide present is increased
E. The ratio of oxygen to nitrogen in the system is increased