JAMB Chemistry Past Questions & Answers - Page 413

2,061.

What is the decrease in volume of air when pyrogallol is shaken with 30.00cm3 of air ?

A.

15.00cm3

B.

6.30cm3

C.

0.63cm3

D.

0.06cm3

Correct answer is B

% volume of O2 in air = 21%
∴ (21/100) * 30 = 6.3

2,062.

Pure solvents are obtained by

A.

Distillation

B.

Condensation

C.

Extraction

D.

Evaporation

Correct answer is A

No explanation has been provided for this answer.

2,063.

Deliquescent substance are used for

A.

Cooling

B.

Wetting

C.

Melting

D.

Drying

Correct answer is D

No explanation has been provided for this answer.

2,064.

The pollution from petroleum spillage in rivers and lakes can best be dispersed by

A.

Pouring detergents

B.

Passing of ships through the area

C.

Pouring organic solvents

D.

Evaporation

Correct answer is A

No explanation has been provided for this answer.

2,065.

Which of the following statements is correct about the average kinetic energy of the molecules of a gas?

A.

It increase with increase in pressure

B.

It increase at constant temperature

C.

It increase with increase in temperature

D.

It increase with increase in volume

Correct answer is C

No explanation has been provided for this answer.