WAEC Chemistry Past Questions & Answers - Page 164

816.

What is the mass of 6.02 x 1024 atoms of magnesium? [Mg = 24, Avogadro constant = 6.02 x 1023 atoms mol-1]

A.

240g

B.

24g

C.

2.4g

D.

0.24g

Correct answer is A

No explanation has been provided for this answer.

817.

The force of attraction between covalent molecules is?

A.

electrostatic attraction

B.

hydrogen bonding

C.

ionic force

D.

van der Waals forces

Correct answer is A

Covalent bond involves the interatomic linkage that results from the sharing of an electron pair between two atoms. The binding arises from the electrostatic attraction of their nuclei for the same electrons.

818.

Water molecules are held together by

A.

covalent bond

B.

hydrogen bond

C.

ionic forces

D.

van der Waals forces

Correct answer is B

No explanation has been provided for this answer.

819.

Arrange the following elements in order of increasing electron affinity: Br2CI2
I 2
F 2

A.

I 2CI2Br2F 2

B.

I 2Br2CI2F 2

C.

CI2 I 2Br2F 2

D.

Br2CI2 I 2 F 2

Correct answer is B

No explanation has been provided for this answer.