What is Δn for the following equation in relating Kc to Kp?

Question

What is Δn for the following equation in relating K_c to K_p?

4 NH₃(g) + 3 O₂(g) ⇌ 2 N₂(g) + 6 H₂O(g)

Answer 1

∆n in this equation is the change in number of moles of gas from the reactant side to the product side.

In this case it is 8 - 7 = +1 (note: sign is important when relating Kc to Kp)