Chapter 6 Key Terms Flashcards
Bomb Calorimeter
Equipment designed to measure energy change of a reaction for combustion at constant volume
calorie (cal)
Unit of energy, the energy required to rause 1 gram of water 1*C. Equal to 4.184 J
Calorie (Cal)
Shorthand notation for kcal, used on nutritional labels
Calorimetry
Experimental procedure to measure heat evolved in a chemical reaction
Chemical Energy
Energy associated with relative positions of electrons and nuclei in atoms and molecules
Coffee Cup Calorimeter
A piece of equipment that measures enthalpy change of a reaction at constant pressure
Endothermic reaction
Reaction that absorbs heat from surroundings
Energy
Capacity to do Work
Enthalpy (H)
Sum of internal energy of a system and product of pressure and volume
Exothermic Reactions
Reaction that releases heat into surroundings
First Law of Thermodynamics
Total energy of the universe is constant
Heat (q)
Flow of energy caused by temperature difference
Heat Capacity (C)
THe quantity of heat required to change a systems temperature by 1*C
Heat of Reaction (DeltaHrxn)
Enthalpy change of chemical reaction
Hess’s Law
Law stating that deltaH of a reaction is the sum of deltaH of all steps
Internal energy (H)
Sum of potential and kinetic energies within the system
Joule (J)
SI unit for energy. 1 kg*m^2/s^2
Kilowatt Hour (kWh)
An energy unit used primarily to express large amounts of energy produced by the flow of electricity
Kinetic energy
The energy of an object associated with movement
Law of Conservation of Energy
law stating energy can never be created or destroyed
Molar heat capacity
Amount of heat to raise temperature of 1 mol of object by 1*C
Potential energy
Energy associated with position or composition of a substance
Pressure-volume work
Work that occurs when volume change takes place against external pressure
Specific head capacity (Cs)
Amount of heat to raise 1g 1*C
Standard Enthalpy Change (DeltaH*)
Change in enthalpy for process when all reactants and products are in standard states
Standard Enthalpy of Formation (detaH*f)
Change in enthalpy when 1 mol of compund forms from elements in standard states
Standard State
Pure gas at pressure 1 atm, or pure substance at 1 atm, a certain temperature, or concentration of 1 M
State function
Function whose value depends only on state, not path
Surroundings
everything in the universe that is not the system of interest
System
point of universe of interest
Thermal energy
Kinetic energy associated with temperature of object
Thermal equilibrium
Point at which there is no net transfer of heat between system and surroundings
Thermochemistry
Chemistry of heat
Work (w)
Result of a force acting through difference
