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## Homework Statement

Suppose you have a mole of water at 25##^{\circ}## at atmospheric pressure. You then raise its temperature to 30##^{\circ}##. Determine the change in Gibbs free energy. To compensate for the change, once can raise the pressure on water, how much pressure you need to increase?

I know the right way to do this problem, but I would like to know what I did wrong initially with the following steps:

I knew ##\Delta G = \Delta H - T\Delta S = \Delta Q - \Delta W_{other}##, so i thought: To raise temperature I'd probably need to provide heat, and since no mention of any non-mechanical work was made in the problem, let's take ##\Delta W_{other} = 0##

Therefore ##\Delta G = \Delta Q = C_p \Delta T##, where ##C_p## was a given.

I would then use the thermodynamic identity to work out the pressure change.

What were the wrong assumptions made?

Assistance is greatly appreciated