1 mole of a hydrocarbon of formula CnH2n was burned completely in oxygen producing carbon dioxide and water vapour only. It required 192g of oxygen. Work out the formula of the hydrocarbon.
i cant find a recent thread of this question.
one answer says:
'CnH2n + X O2 ==> n CO2 + n H2O
balancing oxygen, we have X= 3n/2
192g of oxygen is 6 moles, so 3n/2 = 6 ==> n=4
and the hydrocarbon is C4H8'
why have they done 3n/2?
another answer says:
'192g of oxygen = 12 mole
bCnH2n + aO2 -> xCO2 + yH2O
For every 3 moles of oxygen there are 2 of hydrogen and one of carbon.
:. bCnH2n has 8 moles of hydrogen and 4 of carbon'
why have they said theres 12mol? isnt there 6moles?(192/32, to get 12 they wouldve done 192/16 but thats not right so then they wouldve got 6 mol but that gives c2h4 and thats not right?
thanyou