How many liters of CO2 are produced when 2 L of C3H7OH react with 4 L of oxygen at 50 degrees Celsius under 1 atm of pressure?

Question

I know how to solve gas Stoichiometry problems but I don't know how that changes at different temperatures and pressures.

Answer 1

The different temperatures and pressures don’t really change the approach too much. You just use them to find moles of reactants from the ideal gas law, PV = nRT

Use the 2 L and 4 L of gas to find moles of each.

n = PV/RT = (1atm)(2 L)/(0.0821Larm/Kmol)(323K) = 0.0754 moles of C3H7OH

The O₂ will be twice that (4 L istwice 2L) = 0.1508 moles of oxygen.

Balance the combustion reaction: 2C3H7OH + 9O2 ==> 6CO2 + 8H2O

From here, if you know how to do gas stoichiometry problems, you should be able to moles and liters of CO2 produced.