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.

126.

What is the name of the process by which ammonia is produced on an industrial scale?

A.

Nitrogenation

B.

Ammoniation

C.

Nitrification

D.

Haber process

Correct answer is D

The industrial production of ammonia is known as the Haber process. It involves the reaction of nitrogen gas (N\(_2\)) and hydrogen gas (H\(_2\)) at high temperature and pressure in the presence of a catalyst to produce ammonia (NH\(_3\)).

127.

What is eutrophication?

A.

The release of harmful chemicals into water bodies

B.

The excessive growth of algae due to nutrient enrichment

C.

The presence of heavy metals in water

D.

The formation of oil slicks on water surfaces

Correct answer is B

Eutrophication is the excessive growth of algae and aquatic plants in water bodies due to the increased availability of nutrients like nitrogen and phosphorus. This nutrient enrichment often comes from agricultural runoff, sewage, and industrial discharges.

128.

According to the kinetic theory of gases, the pressure exerted by a gas is due to

A.

The vibrations of gas particles.

B.

The weight of the gas particles

C.

The attractive forces between gas particles

D.

The collisions of gas particles with the container walls

Correct answer is D

In the kinetic theory of gases, the pressure exerted by a gas is a result of the frequent and random collisions of gas particles with the walls of the container. The force of these collisions creates pressure on the container walls.

129.

What is the sum of the oxidation numbers in a neutral compound?

A.

+2

B.

-1

C.

0

D.

+1

Correct answer is C

The sum of the oxidation numbers in a neutral compound is always zero. This is because oxidation numbers represent the charge that an atom would have if all bonding were ionic. In a neutral compound, the total positive charge (from the oxidation numbers of the atoms that have positive oxidation numbers) must equal the total negative charge (from the atoms that have negative oxidation numbers).

130.

Which of the following reactions would be expected to have the highest entropy change?

A.

Liquid → Gas

B.

Solid → Liquid

C.

Gas → Liquid

D.

Gas → Solid

Correct answer is A

The phase change from a liquid to a gas involves an increase in entropy. In the gas phase, molecules have higher degrees of freedom and are more dispersed compared to the liquid phase, resulting in higher entropy change.