Question

100 gram of KNO3 heated to redness. Find volume of oxygen is liberated at 39° C and 765 torr pressure.
2KNO3 → 2KNO2 + O2​

Answer 1

101 g

S+O

2

⟶SO

2

Moles of S =

32g/mol

16g

=0.5 mol

0.5 mol of S requires 0.5 mol of oxygen.

So, we know that sulphur burns in 0.5 mol oxygen.

The thermal decomposition of Pottasium nitrate:

2KNO

3

⟶2KNO

2

+O

2

1 mol of O

2

is produced by 2 mol of KNO

3

0.5mol of O

2

will be produced by 1 mol of KNO

3

Thus, 1 mole of KNO

3

is required to produce the given amount of oxygen.

1 mol of KNO

3

= molar mass of KNO

3

=101 g

Explanation:

I hope U Understand This Answer.