CHE 132 Lecture Notes - Lecture 2: Boltzmann Constant, Activation Energy

• School: Stony Brook University
• Department: Chemistry
• Course: CHE 132
• Professor: Troy Wolfskill

Document Summary

Che 132 : prof. khalifa : lecture 2 - entropy. Spontaneous process - something that occurs naturally without an external energy, is allowed to have a initiator or activation energy. A spontaneous reaction is independent of time; it does not tell us how fast the reaction happens. For example : candle burning, salt dissolving in water, ice melting at room temperature. Non-spontaneous process - something that requires energy from an external source to proceed. Sublimation - phase change from solid to gas. Deposition - phase change from gas to solid. S increases w = number of occupiable sites. Note - if there are zero sites available, then there is no freedom and zero entropy. Extensive means it increases in proportion to amount of material. Raising temperature, volume, and number of atoms lead to more accessible microstates, more configurations, and therefore a larger entropy. Entropy of 2 atoms with 5 possible binding sites each would be doubled.