Question

5 mole of NH₄HS (s) start to decompose at a particular
temperature in a closed vessel. If pressure of NH₃(g) in the
vessel is 2 atm, then Kₚ for the reaction,
NH₄HS (s) ⇋ NH₃(g) + H₂S (g), will be –
(a) 2 (b) 4 (c) 0.4 (d) 0.8

Answer 1

Explanation:

Option [A ] is Correct.......

Answer 2

The Kp of the reaction will be equal to 4 atm².

• Initially there are no gases in the vessel as only NH4HS is present which is a solid.
• Equal moles of NH3 and H2S are produced on decomposition of H2S.
• As the number of moles of NH3 is equal to that of H2S , The partial pressure of NH3 will also be equal to the partial pressure of H2S.
• Kp of the reaction is equal to P(NH3)×P(H2S)
• Hence, Kp = 2×2 = 4 atm²