1. Announcements Lon-Capa: 5th HW assignment due Friday 10/21 by 5 pm.
Lon-Capa: 4th Quiz due Sunday, 1023 by 10 pm. Opens Friday 10/21 at 5 pm.
Exam 2 is Tuesday, October 25; rooms the same as Exam 1; equation sheet posted online.
Office hours Tuesday: 1 pm, not 10 am

2. A Question to Consider
Calculate S and Suniv when 50.0 g of ice at 0C is dropped into g of water at 75C in a perfectly insulated vessel and briefly discuss these numbers to show that all of the ice will indeed spontaneously melt.
Hfusion for ice is 6.02 kJ/mol at 0C and Cp for water is 75.3 J/Kmol
Assume Cp is constant over the temperature range in question.

4. The meaning of Grxn
At constant temperature and pressure the sign indicates the spontaneity of the reaction.
Grxn < 0 means spontaneous
Grxn > 0 means not spontaneous (or spontaneous in the opposite direction)
If we change the temperature we can change the sign of Grxn
The magnitude of Grxn tells us the relative extent of the reaction (recall that K does too!)
If we change the temperature we can change the magnitude of Grxn.

5. Clicker Question Consider the spontaneous reaction:
2KClO3(s)  2KCl(s) + 3O2(g)
Is the reaction endothermic or exothermic?
a) Endothermic
b) Exothermic
c) More information is needed.
d) I do not know how to answer this question.