Chemistry

4. the threshold energy that much be overcome to produce a chemical reaction
5. The standard enthalpy change of reaction (denoted ΔrHo) is the enthalpy change that occurs in a system when one mole of matter
7. a plot of temperature versus time for a substance where energy is added at a constant rate
8. energy due to position or composition
10. the energy of a mass resulting form its motion
13. refers to a reaction where energy (as heat) flows out of the system
14. the enthalpy change that occurs to melt a solid at its melting point

1. The measure, on any of several scales, of the average kinetic energy of the molecules in a sample of material
2. The heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).
3. the energy required to vaporize one mole of a liquid at a pressure of one atmosphere
6. 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. At constant pressure, the change in enthalpy equals the energy flow as heat
9. a devicie used to measure energy changes accompnying chemical and physical changes by observing temperature alterations
11. refers to a reaction where energy (as heat) flows into the system
12. law in going from a particular set of reactants to a particular set of products