Chemistry questions and answers

Chemistry Questions and Answers

Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.

2,936.

Which of the following is a example of a chemical change?

A.

Dissoultion of salt in water

B.

Rusting of iron

C.

Melting of ice

D.

Separating a mixture by distillation

Correct answer is B

No explanation has been provided for this answer.

2,937.

Chromatography is used to separate components of mixtures which differ in their rates of?

A.

diffusion

B.

migration

C.

reaction

D.

sedimentaion

Correct answer is B

No explanation has been provided for this answer.

2,938.

Which of the following reagents will confirm the presence of unsaturation in a compound?

A.

Fehling's solution

B.

Bromine water

C.

Tollen's reagent

D.

Benedict's solution

Correct answer is B

No explanation has been provided for this answer.

2,939.

One mole of a hydrocarbon contains 48 g of carbon. If it vapour density is 28, the hydrocarbon is?

A.

an alkane

B.

an alkene

C.

an alkyne

D.

aromatic (C = 12, H = 1)

Correct answer is B

No explanation has been provided for this answer.

2,940.

The general formula of alkanoates is?

A.

RCHO

B.

R2CO

C.

RCOOH

D.

RCOOR

Correct answer is D

Otherwise known as ESTERS, they are easily gotten from a reaction between the CARBOXYLIC acids and ALCOHOLS

RCOOH + R'OH yields a combination of an ester(RCOOR') and water.