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.

3,526.

22688Ra → x86Rn + α - particle
What is the value of x in the nuclear reaction above?

A.

220

B.

222

C.

226

D.

227

Correct answer is B

22688Ra → 22286Rn + α - particle

3,527.

The shape of s-orbitals is

A.

spherical

B.

elliptical

C.

spiral

D.

circular

Correct answer is A

No explanation has been provided for this answer.

3,528.

An electron can be added to a halogen atom to form a halide ion with

A.

2 valence electrons

B.

3 valence electrons

C.

7 valence electrons

D.

8 valence electrons

Correct answer is D

No explanation has been provided for this answer.

3,529.

A given volume of methane diffuses in 20s. How long will it take the same volume of sulphur (IV) oxide to diffuse under the same conditions?
[C = 12, H = 1, S = 32, O = 16

A.

5s

B.

20s

C.

40s

D.

60s

Correct answer is C

Relative molecular mass of CH4 = 12 * 1 + 4 = 16
Relative molecular mass of SO2 = 32 + 10 *2 = 64
tSO2/tCH4 = √MSO2/MCH4
t/20 = √64/16 = √4
t/20 = 2
∴ t = 20 * 2 = 40sec

3,530.

It is difficult to achieve an orderly arrangement of the molecules of a gas because they?

A.

have no definite shape

B.

have little force of attraction between them

C.

can collide with one another in the container

D.

are too small in size

Correct answer is B

In most cases, there are essentially no attractive forces between particles. This means that a gas has nothing to hold a specific shape or volume.