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.

1,421.

An advantage of detergent over soap is that detergents

A.

are readily available

B.

are in powerdered from

C.

are non-biodegradable

D.

lather readily with water

Correct answer is D

Detergent lather readily with water. Soap does not lather readily with water. Soap is a good cleansing agent in soft water, in hard water it forms scum.

1,422.

Fact and oils are used as raw materials in the following industries except

A.

paint industry

B.

plastic industry

C.

margarine industry

D.

cosmetics industry

Correct answer is B

No explanation has been provided for this answer.

1,423.

The quantity of electricity required to discharge 1 mole of univalent ion is

A.

9,600 C

B.

48,250 C

C.

96,500 C

D.

193,00 C

Correct answer is C

No explanation has been provided for this answer.

1,424.

What is the change in oxidation number of manganes in the reaction represented by the following equation? MnO-4(aq) + 8H+(aq) + 5e- → Mn2+(aq) + 4H2O(l)

A.

+3 to + 2

B.

+ 4 to + 2

C.

+ 5 to + 2

D.

+ 7 to 2

Correct answer is D

No explanation has been provided for this answer.

1,425.

Which of the following statements about the electrolysis of CuSO4(aq) using copper cathode and platinum anode is not correct?

A.

Copper is deposited at the cathode

B.

Oxygen is liberated at the anode

C.

it is used for the purification of copper

D.

The solution becomes acidic

Correct answer is C

For purifying impure copper, the anode electrode is impure copper while the cathode electrode is pure copper, but for this question, two different electrodes were used, hence option C is the correct option to this question.