WAEC Chemistry Past Questions & Answers - Page 168

836.

Consider the reaction below: Vegetable oil \(\frac{H2;NI catalyst}{High temperature}\) product. The reaction is applied in the manufacture of?

A.

drugs

B.

margarine

C.

paraffin wax

D.

soapy detergents

Correct answer is B

This is called hydrogenation. It includes the manufacture of margarine from animal or vegetable fats and oils.

Ethene reacts with hydrogen in the presence of a finely divided nickel catalyst at a temperature of about 150°C. Ethane is produced.

837.

Hydrocarbons which react with ammoniacal copper (l) chloride solution conform to the general molecular formula

A.

CnH2n

B.

CnH2n

C.

CnH2n+2

D.

CnH2n-2

Correct answer is D

No explanation has been provided for this answer.

838.

Alkenes undergo the following reactions except

A.

addition

B.

hydration

C.

polymerization

D.

substitution

Correct answer is D

No explanation has been provided for this answer.

839.

Which of the following pairs of substances can be distinguished by use of NaHCO3 solution?

A.

CH 3CH2OH and HCOOCH3

B.

CH 3CH2OH and CH3COOH

C.

CH3COOH and HCOOH

D.

CH 3CH2OH and CH3OH

Correct answer is B

No explanation has been provided for this answer.

840.

The complete hydrogenation of C 6
H 6 in the presence of nicked catalyst at 200oC gives

A.

C6H8

B.

C 6H10

C.

C 6H 12

D.

C 6H 14

Correct answer is C

No explanation has been provided for this answer.