Mole ConceptHard

Question

Pure FeS2 is burnt with 60% excess air. What is the percentage of N2, by volume, in the gaseous mixture after the reaction? Air contains 20% O2 and 80% N2 by volume.

Options

A.81.94
B.82.8
C.70.4
D.89.3

Solution

4FeS2 + 11O2 → 2Fe2O3 + 8SO2(g)

4 mole (say) 11 mole 8 mole

Final composition of gases:

$O_{2} = 11 \times \frac{60}{100} = 6.6\text{ mole} $$$N_{2} = (11 + 6.6) \times \frac{80}{20} = 70.4\text{ mole}$$

SO2 = 8.0 mole

∴ Total moles of gases = 6.6 + 70.4 + 8.0 = 85

∴ Volume per cent of N2 =$\frac{70.4}{85} \times 100$ = 82.82%

Create a free account to view solution

View Solution Free
Topic: Mole Concept·Practice all Mole Concept questions

More Mole Concept Questions