Question

What volume of oxygen gas is needed to completely combust 0.202 L of butane gas?

Answer 1

We need a stoichiometric equation:

`C_4H_10(g) + 13/2O_2(g) rarr 4CO_2(g) + 5H_2O(l)`

Explanation:

The stoichiometrically balanced equation tells me unequivocally that for each equiv butane, I NEED `13/2` equivs of dioxygen gas for complete combustion. Agreed?

So, since gaseous volume is proportional to the number of moles, at given temperature and pressure, we need a volume of dioxygen gas `=0.202*Lxx13/2="a bit under 1.5 litres"`. How many litres of carbon dioxide gas will result?