What is the expression for K_c for the reaction N2(g) + 3H2(g) 2NH3(g)?

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NEET levelSingle correct optionDifficulty 1 of 3ce001

What is the expression for $K_{c}$ for the reaction $N X_{2} (g) + 3 H X_{2} (g) 2 NH X_{3} (g)$ ?

A $\frac{[ NH X _{3} ]}{[ N X _{2} ] [ H X _{2} ]}$
B $\frac{[ N X _{2} ] [ H X _{2} ] ^{3}}{[ NH X _{3} ] ^{2}}$
C $\frac{[ NH X _{3} ] ^{2}}{[ N X _{2} ] [ H X _{2} ] ^{3}}$
D $\frac{2 [ NH X _{3} ]}{[ N X _{2} ] \cdot 3 [ H X _{2} ]}$

Answer: C

By the law of mass action, product concentrations (raised to their stoichiometric coefficients) appear in the numerator and reactant concentrations in the denominator. Hence

K_{c} = [NH X_{3}]^{2} / ([N X_{2}] [H X_{2}]^{3})

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What is the expression for Kc​ for the reaction NX2​(g)+3HX2​(g)​2NHX3​(g)?

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What is the expression for $K_{c}$ for the reaction $N X_{2} (g) + 3 H X_{2} (g) 2 NH X_{3} (g)$ ?