Heating Curves and Cooling Curves

Okay, I'm going to make this rather short.

Heating curves are reasonably simple to understand. Here's a general graph of a substance being heated.

A (diagonal line): The substance is solid. Its KE is increasing while its PE remains constant. Therefore, the temperature increases but there is no significant change in the distance between the particles.

B (straight line): The substance is melting. Its PE is increasing while its KE remains constant. The particles begin to move further away. The temperature doesn't increase because the substance is too busy melting. I think this part is also called the latent heat of fusion.

C (diagonal line): The substance is a liquid. Its KE is increasing while its PE remains constant.

D (straight line): The substance is boiling. Its PE is increasing while its KE remains constant. I think this part is also called the latent heat of vaporisation.

E (diagonal line): The substance is a gas. Its KE is increasing while its PE remains constant.

Oh yeah, there's also cooling curves. They're basically heating curves backwards (though the axes obviously stay in the same place). I really can't be bothered drawing one, but I will if you want me to.