We use the concentration to calculate the equilibrium constant. This might seems pretty confusing right now, let's look at some examples and see how we can use this equilibrium constant. 2. products are always in the numerator, and reactants are always in the denominator. Solids and liquids are ignored. No units for K eq 6.
Concentrations are always in moles per liter.
In this case, notice that H 2 O is in the gaseous form. If it was in the liquid or the solid state, then we won't use it in the K eq . This is slightly different than the above example. In this case, there is a solid in the equation. Note that the value of the equilibrium constant depends on the temperature.