WAEC Chemistry Past Questions & Answers - Page 246

1,226.

The function of limestone in the extraction of iron in the blast furnace is

A.

removal of the earthly impurities

B.

decomposition of the iron ore

C.

conversion of iron (lll) to iron (ll) compounds

D.

generation of heat for the process

E.

conversion of coke to carbon(ll)oxide

Correct answer is A

No explanation has been provided for this answer.

1,227.

Which of the following is an alloy of mercury?

A.

Stainless steel

B.

Soft solder

C.

Coinage bronze

D.

Amalgam

E.

Duralumin

Correct answer is D

No explanation has been provided for this answer.

1,228.

The following alkanols will yield alkanoic acids on reacting with excess acidified K2Cr2O7 except

A.

CH3CH2OH

B.

(CH3)2CHCH2OH

C.

(CH3)3CCH2OH

D.

(CH3)3COH

E.

CH3CH2CH2CH2OH

Correct answer is D

option D is a tertiary alkanol. tertiary alkanols are resistant to oxidation so cannot react with excess acidified \(K_2Cr_2O_7\) to give any product.

1,229.

In which of the following processes are larger molecules broken down into smaller molecules?

A.

Vulcanization of rubber

B.

Hydrogenation of palm oil

C.

Hydrolysis of starch

D.

Polymerization

E.

Esterification

Correct answer is C

No explanation has been provided for this answer.

1,230.

The gas produced when a mixture of sodium propanoate and soda lime is heated is

A.

methane

B.

pentane

C.

ethane

D.

butene

E.

ethyne

Correct answer is C

So during the presence of methane, sodium ethanoate with soda lime is used, using sodium propanoate with sodium will produce ethane according to the equation below

\(\CH_3CH_2COONa + NaOH → C_2H_6 + Na_2CO_3\)\