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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.

User Gom
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Answer:

Kp = 0.022

Step-by-step 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 = (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 = (0.23atm*0.69atm^3)/(1.84atm^2)

Kp = 0.022

User Salviati
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