How many liters of water vapor can be produced if 13.3 liters of methane gas (CH4) are combusted, if all measurements are taken at the same temperature and pressure? Show all of the work used to solve this problem.

CH4 (g) + 2 O2 (g) CO2 (g) + 2 H2O (g)

Question

How many liters of water vapor can be produced if 13.3 liters of methane gas (CH4) are combusted, if all measurements are taken at the same temperature and pressure? Show all of the work used to solve this problem. 

CH4 (g) + 2 O2 (g) CO2 (g) + 2 H2O (g)

thomaster · Answer

First calculate the amount of moles CH4 you have.
You can do this with the fact that 1 mole gas occupies 22.4 liters. Just divide by 22.4.

So now you have the amount of moles CH4, now you can calculate the amount of moles H2O using the reaction ratio. This is 1 mole CH4 reacts with 2 moles oxygen to produce 1 mole CO2 and 2 moles H2O

So when your input is 1 mol HC4, the output will be 2 mol H2O 

Next you convert mol H2O to liter H2O gas by multiplying the amount of moles with 22.4 

:)

jfraser · Answer

@thomaster is correct, but you can shortcut this by using the standard molar volume. Because all measurements are taken under the same conditions, 13.3L of CH4 will produce twice that volume of H2O, just as 13.3mol of CH4 would produce twice that many moles of H2O.

thomaster · Answer

lol that's much simpler. Can't believe i didn't think of that XD