So these guys will want to convert to decrease the overall concentration of our reactants so that our Q can become our K again. In other words, Q will tend to move towards K. Likewise, if we increase the concentration of products. That means our q will become a less than K.
And since q will want to move towards K, this concentration will tend to decreasing therefore providing a leftward shift in equilibrium. I want to mention one last important note what will happen if we add some other arbitrary molecule that is not present in our reaction? Such as for example, diatomic CO2 in our gas state? Well, to answer this question, let's look at our partial pressure equilibrium constant.