| A | B |
|---|
| energy | the ability to do work or produce heat |
| law of conservation of energy | in any chemical reaction or physical process, energy can be converted from one form to another,but is neither created nor destroyed |
| chemical potential energy | the energy stored in a substance because of its composition |
| heat | the energy that is in the process of flowing from a warmer object to a cooler object |
| calorie | the amount of heat required to raise the the temperature of one gram of pure water by one degree Celsius |
| joule | the SI unit of heat and energy |
| calorimeter | an insulated device that is used to measured the amount of heat released or absorbed during a physical or chemical process |
| thermochemistry | the study of heat changes that accompany chemical reactions and phase changes |
| system | in thermochemistry, the specific part of the universe containing the reaction of the process being studied |
| universe | in thermochemistry, is the system plus the surroundings |
| surroundings | in thernochemistry, includes everything in the universe except the system |
| enthalpy | the heat content of a system at constant pressure |
| enthalpy heat of reaction | the change in enthalpy for a reaction-the difference between the enthalpy of the substances that exist at the end of the reaction and the enthalpy of the substances present at the start |
| enthalpy heat of combustion | the enthalpy change for the complete burning of one mole of a given substance |
| thermochemical equation | a balanced chemical equation that includes the physical states of all the reactants and products that specifies the change in enthalpy |
| molar enthalpy heat of vaporization | the amount of heat required to evaporate one mole of a solid substance |
| molar enthalpy heat of fusion | the amount of heat required to melt one mole of a solid substance |
| Hess's law | states that if two or more thermochemical equations can be added to produce a final equation for a reaction, then the sum of the enthalpy changes for the individual reactions is the enthalpy change for the final reaction |
| standard enthalpy heat of formation | the change in enthalpy tha accompanies the formation of one mole of a compound in its standard state from its constituent elements in their standard states |
| spontaneous process | a physical or chemical change that occurs without outside intervention and may require energy to be supplied to begin the process |
| entropy | a measure of the disorder or randomness of the particles of system |
| law of disorder | states that entropy of the universe must increase as a result of a spontaneous reaction or process |
| free energy | the energy that is available to do work-the difference between the change in enthalpy and the product of the entropy change and the absolute temperature |
| specific heat | the amount of heat required to raise the temperature of one gram of a given substance by one degree Celsius |
