CIE Chemistry (US-0439): Specimen Questions with Answers 72 - 75 of 240

Question number: 72

MCQ▾

Question

Choices

Choice (4) Response

a.

b.

c.

d.

Answer

d.

Explanation

HCl is an acid. Acids give ions when dissolved in water.

Question number: 73

MCQ▾

Question

The Relative Molecular Mass of water is________.

(Given that the Atomic Mass of hydrogen is . and the Atomic Mass of oxygen is . )

Choices

Choice (4) Response

a.

38

b.

28

c.

8

d.

18

Answer

d.

Explanation

2 atoms of hydrogen combine with 1 atom of oxygen to form 1 molecule of water.

=

= .

Thus the Relative Molecular Mass of water is

Question number: 74

MCQ▾

Question

The number of valence electron/electrons present in alkali metals is ________.

Choices

Choice (4) Response

a.

3

b.

4

c.

1

d.

2

Answer

c.

Explanation

Alkali metals have only 1 valence electron.

Question number: 75

Short Answer Question▾

Write in Short

Describe a test, other than measuring pH, which can be carried out on both acid solutions to confirm the explanation given in (b) (i) for the different pH values of the two acids.

Complete the following equations for reactions of these two acids.

[

Explanation