To answer this question, we need to know that the volume occupied by 1 mol of any gas will always be 22.4 L at STP. This value corresponds to the molar volume of the gases.
So we need to transform moles into liters for each compound and then sum those values.
1.5 moles N2 ---- x L
1 mol --- 22.4 L
x = 33.6 L
4.5 moles of CO2 --- x L
1 mol --- 22.4 L
x = 100.8 L
33.6 + 100.8 = 134.4 L
You can also sum 1.5 mol + 4.5 mol and transform it to liters using 22.4 L/mol.
Answer: 134.4 L
When we consider the Standard temperature and pressure (STP), in which the pressure is equal to 1 atm and the temperature is 273 K (0ºC), we have that the volume occupied by 1 mol of any gas will always be 22.4 L. This value corresponds to the molar volume of the gases.
