Question

Which of the following contains the smallest percentage by mass of sulphur?

(A ) SO3

(B) SO2
(C) HS
(D ) H2S207

Answer 1

HS .......................

Answer 2

Given:

Four compounds with different masses of sulphur.

To find:

The compound that contains the smallest percentage by mass of sulphur.

Solution

Let us first find out the percentage of sulphur in each compound by mass.

For SO3, percentage of sulphur = 32/ (32 + 16*3) = 40%

For SO2, percentage of sulphur = 32/ (32 + 16*2) = 50%

For HS, percentage of Sulphur = 32/ (32+ 1) = 97%

For H2S2O7, percentage of Sulphur = (32* 2)/ (1*2 + 32*2 + 16*7) = 36%

Thus H2S2O7 contains the smallest percentage of sulphur by mass.