Question

Ammonium hydrogen sulfide decomposes according to the following reaction, for which Kp = 0.11 at 250°C: NH4HS(s) ⇌ H2S(g) + NH3(g) If 46.5 g of NH4HS(s) is placed in a sealed 5.0−L container, what is the partial pressure of NH3(g) at equilibrium? PNH3 = atm

Answer 1

Answer:

0,33atm

Explanation:

For the reaction:

NH₄HS(s) ⇌ H₂S(g) + NH₃(g)

kp is defined as:

kp = 0.11 = P(H₂S) P(NH₃) (1)

Where P(H₂S) and P(NH₃) are partial pressures of each compound.

In equilibrium, if in your system the only addition is of NH₄HS(s), the partial pressures and the concentration of each compound are:

NH₄HS: I - x

-Where I is an initial concentration that is not relevant for the problem and x is the NH₄HS that reacts-

H₂S(g): x

NH₃(g): x

Replacing in (1):

0.11 = X×X

0.11 = X²

0.33 = X

That means P(NH₃) is 0.33 atm

I hope it helps!