## Textbook question 4.51

$\Delta G^{\circ}= \Delta H^{\circ} - T \Delta S^{\circ}$

$\Delta G^{\circ}= -RT\ln K$

$\Delta G^{\circ}= \sum \Delta G_{f}^{\circ}(products) - \sum \Delta G_{f}^{\circ}(reactants)$

Paige Lee 1A
Posts: 136
Joined: Sat Sep 07, 2019 12:16 am

### Textbook question 4.51

Using values in Appendix 2A, calculate the standard Gibbs free energy for the vaporization of water at 25.0 8C, 100.0 8C, and 150.0 8C. (b) What should the value at 100.0 8C be? (c) Why is there a discrepancy?

Katherine Wu 1H
Posts: 104
Joined: Fri Aug 30, 2019 12:15 am
Been upvoted: 2 times

### Re: Textbook question 4.51

b. the value at 100 celsius should be exactly 0, because this is the normal boiling point of water
c. the discrepancy arises because the enthalpy and entropy values calculated from the tables are not rigorously constant with temperature. better values would be obtained using the actual enthalpy and entropy of vaporization measured at the boiling point.