Question

For the reaction of gaseous nitrogen with gaseous hydrogen to produce gaseous ammonia, the correct equilibrium constant expression is _____

Answer 1

The solution would be like this for this specific problem:

 

First, we need to write out the balanced reaction equation for the problem:

"gaseous nitrogen with gaseous hydrogen to produce gaseous ammonia" 

gaseous nitrogen + gaseous hydrogen = gaseous ammonia 

gaseous nitrogen = N2(g) 
gaseous hydrogen = H2(g) 
gaseous ammonia = NH3(g) 

In here, I’m going to show you how to balance this from start to finish: 

N2(g) + H2(g) ↔ NH3(g) (basic, unbalanced equation that shows reactants and product) 
N2(g) + H2(g) ↔ 2NH3(g) (balances the nitrogens) 
N2(g) + 3H2(g) ↔ 2NH3(g) (balances the hydrogens) => Balanced Equation 

Next, we write the Keq expression of the balanced reaction:

Keq = (∏[products]^n) /(∏[reactants]^n) 
Keq = [NH3]^2 / [[N2][H2]]^3 


Therefore, the correct equilibrium constant expression is Keq = (NH3)2 / (N2)(H2)3.