In this question, we have to find how many liters of Nitrogen gas is used to make 2.00 Liters of NH3, and the first thing we have to do is set up the properly balanced equation:
N2 + 3 H2 -> 2 NH3, now the reaction is balanced
According to the balanced equation, the molar ratio between NH3 and N2 is 2:1, which means with 1 mol of N2, we can produce 2 moles of NH3, but now we have to match the number of moles equivalent to 2 Liters of NH3
At STP (Standard Temperature and Pressure), 1 mol of gas is equal to 22.4 Liters of Volume, which means, 2 moles of gas will be equal to:
22.4 L = 1 mol
2 L = x moles
x = 0.089 moles of NH3 in 2 Liters
Now, according to the molar ratio, if we have 0.089 moles of NH3, we will have:
2 NH3 = 1 N2
0.089 NH3 = x N2
x = 0.0445 moles of N2
Now to find the volume, we will use that information about STP again
1 mol = 22.4 Liters
0.0445 moles = x Liters
x = 1 Liter of Nitrogen gas is required