FeS2+O2→Fe2O3+SO2
Here initial mole of FeS2 is 10.
Applying POAC on O atom,
2(nO2)=3(nFe2O3)+2(nSO2) ...(i)
Applying POAC on Fe atom,
1(nFeS2)=2(nFe2O3) ...(ii)
Using (i) and (ii)
2(nO2)=3(nFeS22)+2(nSO2)
2(nO2)=3(102)+2(20)
2(nO2)=552
Now, moles of air=10020×moles of O2
Volume=10020×552×22.4=3080 L