WAEC Chemistry Past Questions & Answers - Page 242

1,206.

Which of the following is not correct about a catalyst? It

A.

remains unchanged chemically at the end of a reaction

B.

helps to establish equilibrium faster reversible reaction

C.

can start a chemical rection which will normally not take place

D.

is usually specific in its action

E.

alters the rate of chemical reaction

Correct answer is C

No explanation has been provided for this answer.

1,207.

Which of the following statements is not correct about electrolysis?

A.

Reduction occurs at the anode

B.

Anions migrate to the anode

C.

Positive ions migrate to the cathode

D.

Concentration affects the discharge of ions

E.

Electrolytes conduct electric current

Correct answer is A

No explanation has been provided for this answer.

1,208.

In which of the following compounds is the oxidation number of nitrogen equal to + 3?

A.

NO 2

B.

N 2O

C.

NO

D.

HNO2

E.

HNO3

Correct answer is D

No explanation has been provided for this answer.

1,209.

An arrangement of two different metals in aqueous solutions of their salts to produce an electronic current is known as

A.

electrochemical cell

B.

activity series

C.

thermocouple

D.

voltameter

E.

galvanometer

Correct answer is A

No explanation has been provided for this answer.

1,210.

Amphoteric oxides are oxides which

A.

react with water to form acids

B.

react with water to form alkali

C.

show neither acid nor basic properties

D.

react with acids alkalis

E.

contain high proportion of oxygen

Correct answer is D

No explanation has been provided for this answer.