Answer:At STP, a mole of gas takes up 22.4 liters.
(This information can be deducted from ideal gas law)
So 15 liters correspond to x moles:
22.4 —- 1 mole
15 —- x
x = 0.67 moles
The complete combustion is the reaction:
CH4 (for example) + 2 O2 -> CO2 + 2 H2O
it is the same than
1/2 CH4 + O2 -> 1/2 CO2 + H2O
So the dioxide carbon producted will be 0.67/2 moles. Or, it will be 15/2 = 7.5 liters.
Notice that I used CH4 but I might used any organic compound instead. I used CH4 to be more pratical resulting 1 carbon atom in each side of the chemical equation.
Step-by-step explanation: