Question

Ammonia will decompose into nitrogen and hydrogen at high temperature. An industrial chemist studying this reaction fills a flask with of ammonia gas, and when the mixture has come to equilibrium measures the partial pressure of hydrogen gas to be . Calculate the pressure equilibrium constant for the decomposition of ammonia at the final temperature of the mixture. Round your answer to significant digits.

Answer 1

Answer:

Kp = 0.022

Explanation:

Full question: ...With 2.3 atm of ammonia gas at 32. °C. He then raises the temperature, and when the mixture has come to equilibrium measures the partial pressure of hydrogen gas to be 0.69 atm.

The equilibrium of ammonia occurs as follows:

2NH₃(g) ⇄ N₂(g) + 3H₂(g)

Where Kp is defined as:

$Kp = \frac{P_{N_2}P_{H_2}^3}{P_{NH_3}^2}$

Where P represents partial pressure of each gas.

As initial pressure of ammonia is 2.3atm, its equilibrium concentration will be:

P(NH₃) = 2.3atm - 2X

Where X represents reaction coordinate

Thus, pressure of hydrogen and nitrogen is:

P(N₂) = X

P(H₂) = 3X.

As partial pressure of hydrogen is 0.69atm:

3X = 0.69

X = 0.23atm:

P(NH₃) = 2.3atm - 2(0.23atm) = 1.84atm

P(N₂) = 0.23atm

P(H₂) = 0.69atm

$Kp = \frac{0.23atm*0.69atm^3}{1.84atm^2}$

Kp = 0.022