CHEM 123 Chapter Notes - Chapter 5: Equilibrium Constant, Standard Molar Entropy, Boltzmann Equation

• School: UBC
• Department: Chemistry
• Course: CHEM 123
• Professor: Glenn Sammis

Document Summary

Chapter five: spontaneous change: entropy and free energy. Spontaneous process: process that is able to take place in a system left to itself. No external action is required to make process proceed; some may take a long time (i. e. rusting) Nonspontaneous process: process that does not occur naturally. Brought about by intervention from outside system, such as electricity. If the process is spontaneous, the revers is nonspontaneous. Looking at enthalpy change, spontaneous change is the direction in which enthalpy of system decreases (exothermic: exceptions of endothermic spontaneous reactions: Evaporation of liquid diethyl ether from open beaker. Dissolving of ammonium nitrate in water: need to look to other thermodynamic functions as criteria for spontaneous change. Entropy is a function of state (like u and h); has specific value for system whose temperature, pressure, and composition are specified. Entropy change ( s): the difference in entropy between two states of a system.