JAMB Chemistry Past Questions & Answers - Page 416

2,076.

The reaction of carbide with water gives

A.

ethyne

B.

ethene

C.

ethane

D.

ethanal

Correct answer is A

No explanation has been provided for this answer.

2,077.

The chlorinated alkane often used industrially to remove grease is

A.

tetrachloromethane

B.

chloromethane

C.

trichloromethane

D.

dichlorometane

Correct answer is A

No explanation has been provided for this answer.

2,078.

The conditions necessary for the extraction of a water molecule from two molecules of ethanol are

A.

less acid and lower temperature

B.

excess acid and a lower temperature

C.

excess acid and a higher temperature

D.

less acid and a higher temperature

Correct answer is A

- The formation of ethoxyethane ( a sweet smelling liquid) can be considered a dehydration reaction

- This is because the overall reaction is the loss of one molecule of water from two molecules of ethanol

- If the alkanol is in excess instead of the acid in excess, and the temperature is lower.

2,079.

Unsaturated organic compounds are identified by decolourization of

A.

silver bromine and potassium tetraoxomanganate (VII) solutions

B.

bromine water and acidified potassium tetraoxomanganate (VII) solution

C.

silver bromide solution and bromine water

D.

bromine water and alkaline potassium tetraoxomanganate (VII) solution

Correct answer is B

No explanation has been provided for this answer.

2,080.

The repeating unit in natural rubber is

A.

alkyne

B.

isoprene

C.

n-propene

D.

peoprene

Correct answer is B

No explanation has been provided for this answer.