JAMB Chemistry Past Questions & Answers - Page 274

1,366.

In the process of silver-plating a metal M, the metal M is the?

A.

anode and a direct current is used

B.

cathode and an alternating current is used

C.

anode and an alternating current is used

D.

cathode and a direct current is used

Correct answer is D

Plating requires ions to flow through an electrolyte in an electric field. Positive ions flow with the electric field, negative ions against the electric field. This electric field comes from a DC supply connected to the electrodes. While silver plating, Ag is the anode while the metal to be coated is the cathode.

1,367.

Neutralization involves a reaction between H3O+ and?

A.

CI-

B.

OH-

C.

NO3-

D.

CO32-

Correct answer is B

No explanation has been provided for this answer.

1,368.

In general, an increase in temperature increases the solubility of a solute in water because?

A.

more solute molecules collide with each other

B.

most solutes dissolve with the evoltion of heat

C.

more solute molecules dissociate at hihger temperatures

D.

most solutes dissolve with absorption of heat

Correct answer is D

No explanation has been provided for this answer.

1,369.

The difference between colloides and and suspensions is brought out clearly by the fact that while colloids?

A.

do not scatter light, suspensions do

B.

can be separated by filtration, suspension cannot be so separated

C.

can be separated by a membrane, suspensions cannot

D.

do not settle out on standing, suspensions do

Correct answer is D

No explanation has been provided for this answer.

1,370.

When plastics and packaging materials made from chloroethene are burnt in the open, the mixture of gases released into the atmosphere is most likely to contain?

A.

ethane

B.

chlorine

C.

hydrogen chloride

D.

ethene

Correct answer is C

No explanation has been provided for this answer.