CHEM 101 Lecture Notes - Lecture 9: Coffee Cup, Enthalpy, Heat Capacity

• School: Drexel University
• Department: Chemistry
• Course: CHEM 101
• Professor: Monica Ilies

Document Summary

Enthalpy in sign for the forwards reaction. We will mostly be concerned with constant pressure. Represented as where the formula =+comes from. =(cid:1869) (enthalpy=heat gained or lost in the system) For a reverse reaction is equal in magnitude (quantity) but opposite. Hess"s law: is independent of the number of steps involved. A change in enthalpy results from a change in the potential energy of the. Calorimetry: measurement of quantity of heat exchanged during a chemical reaction. Constant volume used to measure heat and can withstand large amounts of pressure. Used to determine the energy content of foods and specific heat. Reactions done in an aqueous solution are done at constant pressure. Styrofoam cup(s), thermometer, glass stirrer and cork lid. Is normally provided per mole of a reaction. To get this, divide by the number of moles in the limiting reagent. Two different objects receive the same amount of heat.