Waec Chemistry Past Questions and Answers

Question 21:

• WAEC 1988

The following are uses of radioactive isotops except for

A. Sterilization of medical equipment
B. Tracing reaction paths
C. Dating elements
D. Radiography
E. Determining equilibrum positions

Question 22:

• WAEC 1988

The main characteristic feature of transition metals is that they

A. Have the same atomic size
B. Are reducing agents
C. From ions easily
D. Have variable oxidation states
E. Are highly electropositive

Question 23:

• WAEC 1988

The following are heavy chemicals except

A. Tetraoxosulphate (IV) acid
B. Caustic soda
C. Sodium trioxocarbonate (IV)
D. Ethene
E. Dyes

Question 24:

• WAEC 1988

What quantity of silver is deposited when 96500C of electricity is passed through a solution containing silver ions? (Ag = 108, 1F = 96500C)

A. 1.08g
B. 40g
C. 10,.8g
D. 21.6g
E. 108g

Question 25:

• WAEC 1988

Bubbling of carbon (IV)oxide into calcium hydroxide solution results in the formation of

A. CaCO₃
B. CuCO₃
C. ZnCO,sub>3
D. Na₂CO₃
E. MgCO₃