JAMB Chemistry Past Questions & Answers - Page 323

1,611.

The haloalkanes used in dry-cleaning industries are?

A.

trichloromethane and tetrachloromethane

B.

chloroethene and dichloroethene

C.

trichloroethene and tetrachloroethene

D.

chloroethane and dichloroethene

Correct answer is A

- Both  trichloromethane and tetrachloromethane are such important organic solvent.

1,612.

One of the major uses of alkane is?

A.

as domestic and industrial fuel

B.

in the hydrogenation of oils

C.

in the textile industries

D.

in the production of plastics

Correct answer is A

- Alkanes will react with Oxygen if they are given sufficient Activation Energy. This will result in a highly Exothermic reaction, producing Carbon Dioxide and Water, which makes Alkanes very useful as fuels.

1,613.

The correct order of increasing boiling points of the following compounds C3H7OH, C7H16 and C4H10 is?

A.

C3H7OH → C4H10 → C7H10

B.

C4H10 → C7H16 → C3H7OH

C.

C7H16 → C3H7OH → C4H10

D.

C4H10 → C3H7OH → C7H16

Correct answer is D

C3H7OH ( PROPANOL) ⇒ 97ºC

 C7H16 ( HEPTANE ) ⇒ 98.42ºC ;and

C4H10 ( BUTANE ) ⇒ -1ºC

1,614.

The final products of the reaction between methane and chlorine in the presence of ultraviolet light are hydrogen chloride and?

A.

tricloromethane

B.

dichloromethane

C.

tetrachloromethane

D.

chloromethane

Correct answer is C

Carbon tetrachloride ( IUPAC: Tetrachloromethane) CCl\(_4\), is the final product obtained in this substitution reaction.

1,615.

Which of the following is used to hasten the ripening of fruit?

A.

Ethene

B.

Ethanol

C.

Ethyne

D.

Ethane

Correct answer is A

No explanation has been provided for this answer.