WAEC Chemistry Past Questions & Answers - Page 248

1,236.

Which of the following is not correct of the reaction represented by the equation below? 2C(s) + O2(g) → 2CO(g); ∆H = - xKJ

A.

there is an increase in entropy

B.

There is anincrease in gaseous volume

C.

Carbon (lV) oxide is produced

D.

The oxidation number of carbon increases from 0 to +2

E.

The reaction is exothermic

Correct answer is C

No explanation has been provided for this answer.

1,238.

Sodium chloride cannot conduct electricity in the solid state because it

A.

is a normal salt

B.

is highly soluble in water

C.

is an electrovalent compound

D.

does not have any effect on litmus

E.

does not contain mobile ions

Correct answer is E

No explanation has been provided for this answer.

1,239.

Alums are classified as

A.

simple salt

B.

acid salts

C.

anhydrous salts

D.

double salts

E.

basic salts

Correct answer is D

No explanation has been provided for this answer.

1,240.

Consider the reaction represented by the equation below: XO + YO → X + YO2 In the reaction, YO acts as

A.

an acidic oxide

B.

a basic oxide

C.

a reducing agent

D.

a weak base

E.

an oxidizing agent

Correct answer is C

No explanation has been provided for this answer.