Now realize that with heating and cooling curves, there are significant differences between temperature and phase changes. Now taking a look at some of the key differences here with temperature changes we have heat being converted into kinetic energy, so the energy of motion and realize that the higher our temperature gets, the higher kinetic energy will be as well.

With temperature changes we have our specific heat capacity formula where Q=MCΔT. Q represents our heat. M can either be grams or moles and it depends on the units. For our specific heat capacity, which is C ΔT is just change in temperature, which is final temperature minus initial temperature.

Now with a phase change, we're going to say that if we look at our heating and cooling curves, we saw that the temperature plateaued. It didn't change. That's because heat is being converted into potential energy and we know that there's a connection between temperature and kinetic energy. So if your temperature is not changing, then your kinetic energy also would not change.

So here our average kinetic energy is constant and temperature is constant. It's not changing with a phase change. We use our new enthalpy formula which is Q=m×ΔH which again can either be in grams or moles times our change in enthalpy, so ΔH. So keep this in mind what temperature changes. We use our heat capacity formula but with phase changes where temperature is remaining constant. We have our enthalpy formula here.