CHEM 101A Lecture Notes - Lecture 9: Stoichiometry, Molar Mass

• School: University of Arizona
• Department: Chemistry
• Course: CHEM 101A
• Professor: Laura Van Dorn

Document Summary

Symbol s is used for entropy and it has unit of cal/molk (kelvin) Physical state of a substance and the number of particles have a large impact on the value of s. The higher the disorder, the higher the entropy and the more the reaction energetically favored. Going from solid to liquid is very favorable. More moles than what you started with is more favorable. The more mixed a substance is the more disorder. One property common to thermodynamically favored processes is that the final state is more disordered or random than the original state. Entropy is the reason why things get messy. Entropy s: the degree of dispersal of matter and energy (entropy) in a system can be quantified experimentally. Liquid water has higher entropy than ice. Entropy of a substance increases with temperature. Greater number of freedom is more entropy. Increase in molecular complexity generally leads to an increase in s. Bigger molecules can also have higher entropy.