64g of oxygen reacts completely with methane gas to form 44g of carbon dioxide gas and 36 g of water vapour. Calculate the amount of methane that takes part in the reaction .

1 answer

CH4+ 2O2 >>> 2H2O + CO2
so for each two moles of Oxyen, you use one mole of CH4 and it yields 2moles H2O + one mole of CO2

YOu got 44 grams of CO2, which is one mole.
You got 36 grams of H2O, which is 2 moles
So you needed two moles of oxygen, or 64 grams, which you used.
So you must have used one mole of CH4, which is 16 grams.