CHEM 1062 Lecture Notes - Lecture 20: Gas Constant, Boltzmann Constant, Exothermic Reaction
Document Summary
Initially, the energy of the universe is constant. Einstein: e = mc^2 revisited: the total mass + energy of the universe is constant. Tell us when a process is spontaneous. Spontaneous process = process that occurs by itself without a continuous addition of energy from the outside. Examples of reactions that only go in 1 direction: paper burning to form carbon dioxide water and heat. The reverse of burning paper is not spontaneous. Rust back into a clean nail at room temperature is not spontaneous. Can be spontaneous at a high temperature. O2 and n2 mix, distribute uniformly in room is spontaneous. Diamond turns to graphite is not spontaneous. Thermodynamics does not tell how quickly processes take, just whether or not they happen. Exothermic reaction = releases heat, delta h is less than 0. H2 (g) + o2 (g) ---> h2o (g) Many but not all exothermic reactions are spontaneous; heat release is not enough to prove spontaneity.
