Excess solid NH4Cl is in equilibrium with its gaseous products in a closed vessel at constant temperature: NH4Cl(s) NH3(g) + HCl(g). The volume of the vessel is doubled and equilibrium is re-established (solid still present). Which statements are correct?

The amount of NH3 gas is doubled

Immediately after the expansion, Q_p = K_p/4

The total gas pressure is half of its original value

The amount of NH3 gas is doubled

Immediately after the expansion, Q_p = K_p/4

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Excess solid $NH X_{4} Cl$ is in equilibrium with its gaseous products in a closed vessel at constant temperature: $NH X_{4} Cl (s) NH X_{3} (g) + HCl (g)$ . The volume of the vessel is doubled and equilibrium is re-established (solid still present). Which statements are correct?

A $K_{p}$ is unchanged
BThe total gas pressure is half of its original value
CThe amount of $NH X_{3}$ gas is doubled
DImmediately after the expansion, $Q_{p} = K_{p} /4$

Answer: A, C, D

K_{p} = p_{NH X_{3}} p_{HCl}

is fixed by temperature, so (A) is true and each partial pressure, hence the total, returns to its original value, making (B) false. With the same pressure and twice the volume, the amount of each gas doubles (C). Right after expansion, each pressure halves, so

Q_{p} = K_{p} /4

(D).

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Excess solid NHX4​Cl is in equilibrium with its gaseous products in a closed vessel at constant temperature: NHX4​Cl(s)​NHX3​(g)+HCl(g). The volume of the vessel is doubled and equilibrium is re-established (solid still present). Which statements are correct?

Answer: A, C, D

More questions on Le Chatelier's principle: effect of concentration, pressure, temperature, inert gas

Excess solid $NH X_{4} Cl$ is in equilibrium with its gaseous products in a closed vessel at constant temperature: $NH X_{4} Cl (s) NH X_{3} (g) + HCl (g)$ . The volume of the vessel is doubled and equilibrium is re-established (solid still present). Which statements are correct?