3. Starting from the expression for dG, obtain an expression for the change of molar Gibbs energy for an ideal gas when it is isothermally compressed/expanded at a temperature T from an initial pressure Pref to a final pressure p. Re-arrange your expression to obtain an expression for Gm(p, T). 4. Use the expression for dG to derive a Maxwell relation. Use this to obtain an expression for and evaluate it for an ideal gas. Comment on your result. T