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Don’t forget… Textbook Read Do text homework

Three Big Topics Stoichiometry: information on “what” happens; allows us to determine amounts of reactants and products. Thermodynamics: information on “why” reactions happen; allows us to make predictions about whether a reaction will occur. Kinetics: information on “how” reactions happen (mechanisms); relates to the speed of reactions.

“Ball on a Hill”

Some Big Ideas Low energy  low in potential energy  more stable. If a system absorbs energy, the natural tendency is to release it. That is, achieving low potential energy is “natural”. Ground state preferred over excited state. Energy is converted from one form to another but is NOT created nor destroyed. First law of thermodynamics. Energy is a state function (heat and work are not).

Thermodynamics vs. Kinetics

Questions To Consider How can we predict which reactions are spontaneous (and what do we mean by spontaneous)? How can we provide support (mathematical and qualitative) for observations? Ice cream melts Coffee cools Why do systems reach equilibrium? That is, why doesn’t the ball go “all the way down the hill”?