Waec Chemistry Past Questions and Answers

Question 11:

• WAEC 1988

Which of the following does not affect the rate of a chemical reaction?

A. Addition or presence of a catalyst
B. Size of the reacting particles
C. The enthalpy change for the reaction
D. Concentration of the reactants
E. Temperatureat which the reaction is carried out

Question 12:

• WAEC 1988

Which of the following does not affect the rate of a chemical reaction?

A. Addition or presence of a catalyst
B. Size of the reacting particles
C. The enthalpy change for the reaction
D. Concentration of the reactants
E. Temperatureat which the reaction is carried out

Question 13:

• WAEC 1988

Given that 32.0g sulphur contains 6.02 x 10 23 sulphur atoms how many atoms are there in 2.70g of aluminium? {Al = 27, S =32}

A. 6.02 x 10 ²³
B. 3.01 x 10²²
C. 6.02 x 10²²
D. 5. 08 x 10²²
E. 3.01 x 10²²

Question 14:

• WAEC 1988

The empirical formula of hydrocarbon containing 0. 12 mole of carbon and 0.36 mole of hydrogen is

A. CH₂
B. CH₃
C. C₂H₂
D. C₂H₄
E. C₂H₆

Question 15:

• WAEC 1988

A salt which loses mass when exposed to air is

A. Hygroscopic
B. Deliquescent
C. Efflorescent
D. Fluorescent
E. Effervescent