Chemistry Vocabulary

2. the enthalpy change that occurs to melt a solid at its melting point
7. the measure, on any of several scales, of the average kinetic energy of the molecules in a sample of material
9. the energy required to vaporize one mole of a liquid at a pressure of one atmosphere
11. refers to a reaction where energy (as heat) flows into the system
12. a plot of temperature versus time for a substance where energy is added at a constant rate
13. refers to a reaction where energy (as heat) flows out of the system

1. a device used to measure energy changes accompnying chemical and physical changes by observing temperature alterations
2. the change in the enthalpy of a chemical reaction that occurs at a constant pressure
3. a property of a system equal to E + PV, where E is the internal energy of the system, P is the pressure, and V is the volume of the system
4. the amount of energy required to elevate the temperature of one gram of a substance one degree Celsius
5. energy due to position or composition
6. in going from a particular set of reactants to a particular set of products, the enthalpy change is the same whether the reaction takes place in one step or in a series of steps
8. the energy of a mass resulting from its motion
10. the threshold energy that much be overcome to produce a chemical reaction