CHEMISTRY COMMUNITY

Can someone please explain how to calculate the entropy through different phase changes using the heating curve as a guide?
Thanks!

Entropy change through heating curve is similar to that of calculating enthalpy change. For phase changes, you would use Delta S= qrev/T as temperature is constant. You can calculate qrev using the enthalpy of fusion/vaporization/whatever situation is. For temperature changes, you would use Delta S= nClnT2/T1, with C being the heat capacity (either constant volume/pressure depending on the situation) of that state.

you would need to add the phase change and then the how much entropy it took to raise the temperature. so Delta s = q/t + Delta s= nCln(T2/T1). Don't forget to change temperature to kelvin.

When there is a phase change you use the equation S = qrev/T because the temperature is constant. You use S = nClnT2/T1 when the temperature does change.