CHEM 1050 Lecture Notes - Lecture 11: Lattice Energy

• School: University of Guelph
• Department: Chemistry
• Course: CHEM 1050
• Professor: Mario Monteiro

Document Summary

Slg lib 61 (in basement) 4:30-7 tonight. Entropy is associated with motions within a molecule. At absolute zero there is no motion (pure crystalline material) 3rd law: entropy of pure crystal is zero at zero kelvin. We saw that h can be found experimentally (bomb calorimetry). There is no comparable way to find s; but because we know that s is a state function and that s is zero at zero kelvin we can calculate s. So we have seen that spontaneity is controlled by h and s. We have said up to now that processes that go towards equilibrium (spontaneous processes) have a: But when g = 0 the reaction is at equilibrium. And when g is positive the reaction is non-spontaneous in the forward direction. This means work is needed but the reverse reaction is spontaneous. G is also a state function (there are tables available)