WAEC Chemistry Past Questions & Answers - Page 187

931.

Which of the following processes will pollute water?

A.

Exposure of a body of water ultraviolet rays

B.

Discharge of industrial effluents effluents into water ways

C.

Passage of river water through a send bed

D.

Addition of a measured quantity of chlorine to water

Correct answer is B

No explanation has been provided for this answer.

932.

What are the two gases associated with the formation of acid rain?

A.

CO2 and HCI

B.

CO2 and N2

C.

CO2 and NO2

D.

HCI ans SO2

Correct answer is C

No explanation has been provided for this answer.

933.

When a sample of water was boiled, it lathered more readily with soap. it can be concluded that the sample most likely contained

A.

magnesium tetraoxosulphate (VI)

B.

suspended solids

C.

Organic impurities

D.

calcium hydrogentrioxocarbonate (IV)

Correct answer is D

No explanation has been provided for this answer.

934.

What is the main impurity in haematite?

A.

CaSiO3

B.

CaCO3

C.

SiO3

D.

Fe2O3

Correct answer is C

No explanation has been provided for this answer.

935.

Which of the following compound is used for removing impurities from bauxite?

A.

NaOH

B.

CaCO3

C.

Na3AIF6

D.

H2SO4

Correct answer is A

No explanation has been provided for this answer.