Question

One of the most important chemical reactions is the Haber process, in which N2 and H2 are converted to ammonia which is used in the production of fertilizers. Consider that you have just produced 170 g of NH3 in a 50.0 L tank at 400.0 C. What was the total pressure of the gases that reacted to produce this ammonia? N2(g) + 3 H2(g) ----> 2 NH3(l)a) 221 b) 13 c) 22 d) 11 e) 5.5

Answer 1

Answer:

c) 22

Explanation:

Let's consider the following balanced equation.

N₂(g) + 3 H₂(g) ----> 2 NH₃(l)

According to the balanced equation, 34.0 g of NH₃ are produced by 1 mol of N₂. For 170 g of NH₃:

$170gNH_{3}.\frac{1molN_{2}}{34.0gNH_{3}} =5.00molN_{2}$

According to the balanced equation, 34.0 g of NH₃ are produced by 3 moles of H₂. For 170 g of NH₃:

$170gNH_{3}.\frac{3molH_{2}}{34.0gNH_{3}} =15.0molH_{2}$

The total gaseous moles before the reaction were 5.00 mol + 15.0 mol = 20.0 mol.

We can calculate the pressure (P) using the ideal gas equation.

P.V = n.R.T

where

V is the volume (50.0 L)

n is the number of moles (20.0 mol)

R is the ideal gas constant (0.08206atm.L/mol.K)

T is the absolute temperature (400.0 + 273.15 = 673.2K)

$P=\frac{n.R.T}{V} =\frac{20.0mol\times (0.08206atm.L/mol.K)\times 673.2K ) }{50.0L} =22.0atm$