WAEC Chemistry Past Questions & Answers - Page 124

616.

The following substances are examples of addition polymer except

A.

nylon

B.

perspex

C.

polyethene

D.

polychloroethene

Correct answer is A

Every option, except nylon (which is a condensation polymer), is an addition polymer.

617.

Which of the following separation techniques would show that black ink is a mixture of chemical compounds?

A.

Crystallization

B.

Chromatography

C.

Filtration

D.

Sublimation

Correct answer is B

No explanation has been provided for this answer.

618.

Which of the following compounds would react with ethanoic acid to give a sweet smelling liquid?

A.

Alkane

B.

Alkanol

C.

Alkanal

D.

Alkyne

Correct answer is B

No explanation has been provided for this answer.

619.

Which of the following compounds determines the octane rating of petrol?

A.

1,2,3 - trimethlpentane

B.

2,3,5 - trimethyloctane

C.

2,3,5 - trimethylpentane

D.

2,2,4 - trimethylpentane

Correct answer is D

No explanation has been provided for this answer.

620.

Consider the following electrochemical cell notation: M(s) / M2+ (aq)// H+ (aq)/ H2(g). The value of the electrode potential is positive when?

A.

electrons flow from the metal electrode, M(s) to hydrogen electrode, H2(g)

B.

electrons fow from hydrogen electrode, H2(g) to metal electrode, M(s)

C.

the flow of current is high

D.

there is equilibrium between the flow of electrons from the hydrogen electrode, H2(g) to metal electrode, M(s)

Correct answer is B

No explanation has been provided for this answer.