Thermochemistry
The study of the relationships and chemistry energy.
Energy
The capacity to do work.
Work
The result of the force acting through a distance.
Heat
The flow of energy caused by a temperature difference.
Kinetic energy
Energy associated with the motion of an object.
Thermal energy
The energy associated with the temperature of an object.
Potential energy
Energy associated with position or composition of the object.
Chemical energy
The energy associated with the relative positions of electrons and in atoms and molecules. ( Is also a form of potential energy)
Law of conservation of energy
Energy can be neither created nor destroyed.
system
In thermodynamics, the portion of the universe which is singled out for investigation.
Surroundings
In thermodynamics, everything in the universe which exist outside the system under investigation.
calorie (cal)
A unit of energy defined as the amount of energy required to raise one gram of water 1 degree Celsius; equal to 4.184 J.
Calorie (Cal)
Shorthand notion for kilocalorie (kcal), or 1000 cal; also called the nutritional calorie, the unit of energy use on nutritional labels.
Kilowatt-hour (kWh)
An energy unit used primarily to express large amounts of energy produced by the flow of energy; equivalent to 3.60 x 10^6 J.
Joule (J)
The SI unit for energy: equal to 1 kilogram x m^2/s^2.
First law of thermodynamics
The total energy of the universe constant.
Thermodynamics
The general study of energy and its interconversions.
Internal energy (E)
The sum of the kinetic and potential energies of all of the particles that compose the system. (Is a state function.)
State function
Its value depends only on the state of the system, not on how the system arrived at that state.
Thermal equilibrium
The point at which there is no additional net transfer of heat between a system and its surroundings.
Heat capacity (C)
The quantity of heat required to change its temperature by 1�C.
Specific heat capacity
The amount of heat required to raise the temperature of 1 g of the substance by 1�C.
Molar heat capacity
The amount of heat required to raise the temperature of one mole of a substance by 1�C. (Units are J/mol x �C.)
Pressure-volume work
The work that occurs when a volume change takes place against an external pressure.
Bomb calorimeter
A piece of equipment designed to measure the internal energy of the system for combustion reactions.
Calorimetry
The thermal energy exchange between the reaction (defined as the system) and the surroundings is measured by observing the change in temperature of the surroundings.
enthalpy (H)
The sum of its internal energy and the product of its pressure and volume.
Endothermic reaction
A chemical reaction with positive enthalpy, absorbs heat from his surroundings.
Exothermic reaction
A chemical reaction with negative enthalpy , gives off heat with surroundings.
Enthalpy of reaction (or heat of reaction)
The enthalpy change for a chemical reaction. (It is in extensive property.)
Coffee-cup Calorimeter
A piece of equipment designed to measure enthalpy(rxn) for reactions at constant pressure.
Hess's law
The law stating that if a chemical reaction can be expressed as the sum of a series of steps, then enthalpy(rxn) for the overall equation is the sum of the heats of reactions for each step.
Standard state
For a gas, the standard state is the pure gas at a pressure of exactly 1 atm; for a liquid or solid the standard state is the pure substance in its most stable form at a pressure of 1 atm and the temperature of interest (often taken to be 25�C); for a sub
Standard Enthalpy change
The change in entropy for a process when all reactants and products are in their standard states.
Standard Enthalpy of formation
The change in empathy when 1 mol of a compound forms from its constituent elements in their standard states.