# Change of Internal Energy, Entropy, Volume with Temperature

The two figures show Cp VS T for various transitions. I need to know what the graph would look like for: 1. u (internal energy) vs T 2. S (Entropy) vs T 3. and V vs T for a first order (discontinuous) transition.

Extra Info:

FOr the equilibrium phase transitions at constant T and P (temperature and pressure) the transition is accompanied by a transfer of heat (q doesn't equal 0) between system and surroundings; also, the sytem generally undergoes a volume change. Such transitions with ΔH doesn't equal 0 are called first order or discontinuous. For a first order transition Cp = (dH/dT)p of the two phases is observed to differ. Cp may either increase (as in the transition of ice to water) or decrease (as in water to steam) on going from the low T to the high T phase. Right at the transition temp. Cp = dq/dT is infinite, since the non zero latent heat is absorbed by the system with no temperature change.

Certain speacial phase transitions occur with q = ΔH = TΔS = 0 and with ΔV = 0. There are called continuous transitions. FOr such a transition, the Clapeyron equation is meaningless. For a higher order transitions are either second order transitions or lambda transitions.

I am using Physical Chemistry

Ira N. Levine

Chapter 7 and 8

https://brainmass.com/chemistry/physical-chemistry/change-internal-energy-entropy-volume-temperature-59285

#### Solution Summary

It investigates the change of change of internal energy, Entropy, volume with temperature for the first order (discontinuous) transition, respectively.