Chapter 17 Vocab Flashcards
Chemical potential energy
The energy stored in the chemical bonds of a substance
Thermochemistry
The study of energy changes that occur during chemical reactions and changes in state
Heat
Represented by q, is the energy that transfers from one object to another because of a temperature difference between them
System
The part of the universe on which you focus your attention
Surroundings
Include everything else in the universe
Law of conservation of energy
States that in any chemical or physical process, energy is neither created nor destroyed
Endothermic process
A system that absorbs heat from it’s surroundings
Ectothermic process
A system that releases heat to it’s surroundings
Heat capacity
The amount of heat needed to increase the temperature of and object exactly 1degree C
Specific heat
The amount of heat it takes to raise the temperature 1g of the substance 1 degree C
What is the equation to find specific heat?
Heat(joules or calories)/ mass(g) X change in temperature(degreesC)
Calorimetry
The precise measurement of heat flow into or out of a system for chemical and physical processes
Calorimeter
The insulated device used to measure the absorption or release of heat in chemical or physical processes
Enthalpy(H)
The heat content of a system at constant pressure is the same as this
Thermochemical equation
A chemical equation that includes the enthalpy change
Heat of reaction
The enthalpy change for the chemical equation exactly as it is written
Heat of combustion
The heat of reaction for the complete burning of one mole of a substance
Molar heat fusion
The heat absorbed by one mole of a solid substance as it melts to a liquid at a constant temperature
Molar heat solidification
The heat lost when 1 mole of a liquid solidifies at a constant temperature
Molar heat vaporization
The amount of heat necessary to vaporize one mole of a given liquid
Molar heat condensation
The amount of heat released when 1 mole of vapor condenses at the normal boiling point
Molar heat solution
The enthalpy change caused by dissolution of one mole of substance
Hess’s law of heat summation
States that you add two or more thermochemical equations to give a final equation, then you can also add the heats of reaction to give the final heat of reaction
Standard heat of formation
The change in enthalpy that accompanies the formation of one mole of a compound from it’s elements with all substances in their standard states at 25 degreesC
