When 50 gm of a sample of sulphur was burnt in air 4% of the sample was left over. Calculate the volume of air required at STP containing 21% oxygen by volume.

When 50 grams of sulphur was burnt in air, 4% of the impure residue is left over. Calculate the volume of air required at STP containing 21% of oxygen by volume.

Percentage of oxygen in air by volume…………..

40 grams of a sample of carbon on combustion left 10 % of it unreacted . The volume of oxygen required at STP for this combustion reaction is

The number of moles of oxygen in 1 L of air containing 21% oxygen by volume, in standard conditions, is