WAEC Chemistry Past Questions & Answers - Page 227

1,131.

Which of the following will produce oxygen and hydrogen during its electrolysis using platinum electrode?

A.

Glucose solution

B.

Aqueous copper (ll) tetraoxosulphate (IV)

C.

Dilute sodium chloride solution

D.

Concentrated hydrochloric acid

E.

Dilute copper (ll) chloride solution

Correct answer is C

No explanation has been provided for this answer.

1,132.

What is the function of sulphur (IV) oxide in the reaction represented by the following equation? SO 2(aq) + 2H2S(g) → 3S (s) + 2H 2O (l)

A.

Dehydrating agent

B.

Oxidising agent

C.

Bleaching agent

D.

Acid

E.

Precipitant

Correct answer is B

No explanation has been provided for this answer.

1,133.

Which of the following methods is suitable for the preparation of an insoluble salt?

A.

Action of an acid on a metal

B.

Double decomposition

C.

Neutralisation

D.

Action of an acid on a trioxocarbonate (IV)

E.

Action of an acid on an oxide

Correct answer is B

No explanation has been provided for this answer.

1,134.

Which of the following is not a property of trioxonitrate (V) salts?

A.

Positive reaction to the brown ring test

B.

Ability to dissolve in cold water

C.

Decomposition on being strongly heated

D.

Production of effervescence with saturated Na2CO3 solution

E.

Evolution of gas with concentrated H2SO4 and copper turnings

Correct answer is D

No explanation has been provided for this answer.

1,135.

The following oxides react with water except

A.

Na2O

B.

SO3

C.

NO2

D.

CO2

E.

CuO

Correct answer is E

No explanation has been provided for this answer.