What Happens to change in Pressure. Well, it Zero so Change and Energy Is simply change in Internal Energy. So there is a Transfert Energy into a system. All the Energy is transferer In Increasing Internal Energy Bar System and Because Internal Energy Is related to Kinetic Energy and Kinetic Energy is Related to Temperature increasing Internal Energy increases America Energy and that Increases Temperature. So all the Energy In it Cas Valium Goes in Through Increasing Temperature no Pv Work is Done no expansion is done it constant pressure. However according to the ideal gasa temperature must change as well and a value must change.