Calculate K_C for N2, H2 System: 10.7M^2, 4.00M^2, 2.67M^2, 1.67M^2

[ultimateguy]

Homework Statement

$$N_{2(g)}$$, 0.32M and $$H_{2(g)}$$, 0.66M are placed in a reaction vessel. The system reaches equilibrium when $$[H_{2(g)}]$$ = 0.30M. Calculate $$K_C$$

a) 10.7$$M^2$$
b) 4.00$$M^2$$
c) 2.67$$M^2$$
d) 1.67$$M^2$$

Homework Equations

Equilibrium constant formula

The Attempt at a Solution

This is just messing me up because the chemical equation isn't given. If I don't know the products, how do I get the equilibrium constant?

 

[f(x)]

i s'pose this is the famous haber's process eqn.
N2+3H2---->2NH3

(and this is reversible)