WAEC Past Questions and Answers - Page 1610

8,046.

When alkynes are hydrogenated completely, they produce compounds with the general molecular formula

A.

C nH n

B.

C nH 2n+2

C.

CnH 2n

D.

CnH2n-2

Correct answer is B

when alkyne(\(C_nH_{2n - 2}\)) are hydrogenated completely, alkanes( \(C_nH_{2n + 2}\)) are produced.

8,047.

Which of the following compounds can be represented by the molecular formula C2H6O?

A.

Propanel

B.

Ethanol

C.

Methanoic acid

D.

Glucose

Correct answer is B

No explanation has been provided for this answer.

8,048.

Which of the following processes takes place during the production of margarine from vegetable oils?

A.

Esterification

B.

Hydrolysis

C.

Hydrogenation

D.

Saponification

Correct answer is C

No explanation has been provided for this answer.

8,049.

When concentrated sodium chloride solution is electrolysed using inert electrodes the products are?

A.

oxygen and hydrogen

B.

hydrogen and oxygen

C.

sodium and oxygen

D.

soduim hydroxide, hydrogen and chlorine

Correct answer is D

When concentrated NaCl solution undergoes electrolysis, sodium hydroxide and hydrogen are produced at the cathode while chlorine is produced at the anode.

8,050.

If two metallic ions of the same concentration migrate to a graphite cathode, the one that would be preferentially discharged is the one that has the

A.

smaller mass

B.

lower electrical charge

C.

greater stability in solution

D.

stronger tendency to accept electrons

Correct answer is D

No explanation has been provided for this answer.