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.

1,121.

The use of sulphur to vulcanize rubber is mad to make it

A.

blacker

B.

cheaper

C.

more elastic

D.

tougher

E.

softer

Correct answer is D

No explanation has been provided for this answer.

1,122.

The atomic number of iron is 56. The number of unpaired electrons in the Fe3+ ion is

A.

1

B.

2

C.

3

D.

4

E.

5

Correct answer is E

-There are 4 unpaired electrons in Fe

-However; 5 unpaired electrons are present in Fe3+

1,123.

Animal charcoal differs from wood charcoal in that it

A.

has a dark colour

B.

has a high carbon content

C.

is a good absorbent

D.

is crystalline.

E.

is rich in phosphate content

Correct answer is E

Animal charcoal or bone black is the carbonaceous residue obtained by the dry distillation of bones. It contains only about 10% carbon, the remaining being calcium and magnesium phosphates (80%) and other inorganic material originally present in the bones.

1,124.

Which statement BEST describes the process of oxidation?

A.

addition of hydrogen

B.

loss of oxygen

C.

decrease in oxidation number

D.

loss of electrons

E.

gain of elections.

Correct answer is D

No explanation has been provided for this answer.

1,125.

The decreasing order of the oxidising power of the halogens is

A.

Br>I>Cl>F

B.

F>I>Cl>Br

C.

F>Cl>Br>l

D.

I>Br>Cl>F

E.

Cl>Br>F>I

Correct answer is C

No explanation has been provided for this answer.