Chemistry Equilibrium

Question

N2(g) + 3H2 (g) ----> 2NH3 (g) , the equilibrium constant value (K) was calculated to be 2.0×10^-8 at a given temperature.

1.What is the value of K for the reverse reaction at the same temperature?

Answer 1

When you manipulate a chemical equation / reaction, here are the rules you should know.

1. If you multiply the reaction by a number (n), the K for that reaction is the K for the original raised to the n power,
2. If you reverse the reaction, the K for the new reaction is the reciprocal of the original K
3. If you divide the reaction by a number (n), the K for the new reaction is the nth root of the K for the original reaction

In this example, you are reversing the reaction so the K for the reverse reaction is 1 / original K

K = 1 / 2.0x10^-8 = 5.0x10⁷