Question

2. What volume of air at 1 atm and 273 K containing 21% of oxygen by volume is required to
completely burn sulphur (S,) present in 200 g of sample, which contains 20% inert material
which does not burn. Sulphur burns according to the reaction​

Answer 1

Complete question:

What volume of air at 1 atm and 273 K containing 21% of oxygen by volume is required to  completely burn sulfur (S₈) present in 200 g of sample, which contains 20% inert material  which does not burn. Sulfur burns according to the reaction​ 1/8 S₈ (s) + O₂ (g) → SO₂ (g).

Answer:

The volume of air required is 533.33 Liter.

Explanation:

From question, 200 g of sample, which contains 20% inert material. Thus, pure material is 80%

⇒ 80/100 × 200 = 160 g

The chemical equation of the question is:

S₈ + 8O₂ → 8 SO₂

1 mole of S₈ reacts with 8 moles of O₂

S₈ = 32 × 8 = 256 g

256 g of S₈ reacts with 8 moles of O₂

1 g of S₈ reacts with 8/256 moles of O₂

160 g of S₈ reacts with 8/256 × 160 moles of O₂

160 g of S₈ reacts with 5 moles of O₂

Now,

1 mole = 22.4 L

5 moles of O₂ = 5 × 22.4 = 112 Liter of O₂

21 liter of O₂ is present in 100 liter of air.

1 liter of O₂ is present in 100/21 liter of air.

∴ 112 Liter of O₂ is present in 100/21 × 112 liter of air ⇒ 112 Liter of O₂ is present in 533.33 liter of air