Enthalpy definitions
Enthalpy of formation
Enthalpy change associated with forming 1 mol of compound from its elements under standard conditions
Enthalpy of atomisation
Ethalpy change associated with forming 1 mol of gaseos atoms from element in standard state under standard conditions
1st ionisation energy
Enthalpy change associated with removing 1 mol of e-s to form 1 mol of gaseous 1+ ions from 1 mol of gaseous atoms under standard conditions
1st electron affinity
Enthalpy change associated with 1 mol of gaseous atoms gaining 1 mol of e-s to form 1 mol of gaseous 1- ions under standard conditions
Enthalpy of solution
Enthalpy change associated with dissolving 1 mol of ionic solid in solvent to ensure separation between ions
Lattice enthalpy
Enthalpy change assocaited with forming 1 mol of ionic solid from gaseous ions under standard conditions
Enthalpy of hydration
Enthalpy change when 1 mols of gaseous ions become dissolved in solvent to form 1 mol of aqueous ions
Entropy
Measure of dispersal of energy within a system - more disorderd = higher entropy
Gibb's Free Energy
quantifies balance between entropy and enthalpy as an indicator of feasibility of a reaction
delta G < 0
reaction is feasible
delta G > 0
reaction is not feasible