WAEC Chemistry Past Questions & Answers - Page 139

691.

Rare gases are stable because they

A.

contain equal number of protons and neutrons

B.

contain more electrons than protons

C.

are chemically active

D.

have octet structure

Correct answer is D

No explanation has been provided for this answer.

692.

An element with the electron configuration of 1s 22s 22p 6 would have a combining power of

A.

0

B.

2

C.

6

D.

8

Correct answer is A

No explanation has been provided for this answer.

693.

Which of the following ions has the electron configuration 2,8,8?

A.

Na+

B.

Mg2+

C.

F-

D.

CI-

Correct answer is D

Chlorine(Cl) has configuration 2,8,7 but Chlorine ion (Cl-) has 18 electrons and configuration 2,8,8.

694.

What type of reaction is represented by the following equation?\(\frac{2}{1}\)D\(\frac{3}{1}\)H → \(\frac{4}{4}\)He + \(\frac{1}{0}\)n + energy

A.

Nuclear fission

B.

Nuclar fusion

C.

Radioactive decay

D.

Spontaneous decay

Correct answer is B

No explanation has been provided for this answer.

695.

Which of the following electrons configurations correctly represents an inert element?

A.

1s22s22p4

B.

1s22s22p63s2

C.

1s22s22p63s23p4

D.

1s22s22p6

Correct answer is D

No explanation has been provided for this answer.