What do you predict will happen when a crystal of potassium nitrate is added to the saturated solution as it cooled? what might happen if no crystal were present?

If you add a potassium nitrate and saturated solution you will make a super-saturated solution of potassium nitrate. But what to expect with this process of adding these 2. It is that the result of this solution made/forms bigger crystals that have pointed ends. If there is no appearance of the crystal it shows that the solution is not yet cooled. 

Neither model is able to show the reactivity of potassium.