This is from the interactive syllabus. Remember for standard values you must state under standard conditions i.e. 25 0C 1 atm and any solutions 1 mol/dm3.
Energy Definitions
It should be noted that many of the energy definitions can be considered in the reverse direction with a corresponding change of sign for the energy. Bond formation = exothermic ΔH negative, bond cleavage = endothermic ΔH positive
Enthalpy of vaporisation
The energy required to vaporise one mole of a liquid
Enthalpy of atomisation
The energy required to produce one mole of gaseous atoms from an element in its standard state
Bond dissociation enthalpy
The energy change when one mole of a specific bond is broken or created
Bond enthalpy
The average energy change when one mole of a specific type of bond is broken or created.
Enthalpy of Combustion
The energy released when one mole of a compound is burned in excess oxygen
Enthalpy of formation
The energy change when one mole of a compound is formed from its constituent elements in their standard states
Enthalpy of solution
The energy change when one mole of a substance is dissolved in an infinite amount of water
Hydration enthalpy
The energy change when a particle is taken from infinite separation in the gaseous state to its position in an aqueous lattice
1st Ionisation energy
The energy required to produce one mole of gaseous ions from one mole of gaseous atoms by removal of one mole of electrons
Lattice enthalpy
The energy change when one mole of an ionic substance is broken into its constituent atoms at infinite separation.
