Oxygen required for 1t/ day =‌32/12=2.6667 moles Amount of air required for combustion of carbon =2.6667×350=933.33 tonnes/day Similarly, for hydrogen   ‌
32
4
×100=800 for Sulphur   ‌
32
32
×60=60 for nitrogen   
32
14
×30=68.57 ∴ total oxygen required
=933.34+800+60+68.57≈1862t/day
Available amount of oxygen =260t/day ∴ required amount of oxygen =1862−260=1602t/day ∴ Amount of air required =1602/.23=6965.2 tonnes/day