The equilibrium constant expression for a gas reaction is,
Write the balanced chemical equation corresponding to this expression.
For a chemical change,
aA + bB ⇌ cC + dD
Equilibrium constant Kc for the reaction,
Kc = 
In question, expression for equilibrium constant is given as,
Kc =
Comparing the power of each concentration term we can find the chemical reaction.
The reaction here is given by,
4NO + 6H2O ⇌ 4NH3 + 5O2
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