CHEM 1A03 Study Guide - Midterm Guide: Chemical Energy, Chemical Equation, Enthalpy

• School: McMaster University
• Department: Chemistry
• Course: CHEM 1A03
• Professor: David Brock

Document Summary

Nearly every chemical reaction occurs with either the absorption or release of energy. The study of such energy transfers is thermochemistry. In chemistry, the balanced chemical equation indicates the chemical system. Everything else in the universe is the surroundings. Often the chemical system is separated from surroundings by a boundary, which prevents energy transfer and insulates the system (e. g. styrofoam). The flow of energy is controlled, allowing researchers to measure it. Energy is defined as the ability to do work, is measured in joules (j). The first law of thermodynamics states that energy cannot be created or destroyed but only change forms (e. g. thermal energy can be converted to chemical energy). Chemical energy describes the potential energy that is contained within a compound. A more reactive substance contains greater chemical potential to undergo a reaction. A substance that is very stable contains little chemical potential energy.