As a substance is subjected to pressure and/or temperature changes, it may undergo condensation, deposition, freezing, melting, sublimation, or…

8. As a substance is subjected to pressure and/or temperature changes, it may undergo condensation, deposition, freezing, melting, sublimation, or vaporization. (a) Consider the phase diagra m shown below and state the changes that take place upon going from points A to B to C to D.
(b) Is the transition from A to B exothermic or endothermic?
Attachment 1
Attachment 2