Now, the reaction quotient q is also just like the equilibrium constant k, the ratio of the concentration of products to the concentration of reactants. But unlike our k, q does not refer to the equilibrium concentration. Now, if we look at the following reaction, that is not an equilibrium in which x moles of A react with y moles of B to form our products c and d, both having z and w moles respectively. Now our quotient, our reaction quotient is the same thing as our equilibrium constant in the sense that it's a ratio. It's the ratio of this guy times the ratio. It's the concentration of this guy times the concentration of this guy divided by the concentration of A times the concentration of B.