Definitions

• Enthalpy change of formation

  The enthalpy change when 1 mole of a compound is formed from its constituent elements, with all substances in their standard states
• Lattice enthalpy of dissociation

  The enthalpy change when 1 mole of a solid ionic compound is dissociated into it’s gaseous ions under standard conditions
• Lattice enthalpy of formation

  The enthalpy change when 1 mole of a solid ionic compound is formed from it’s gaseous ions under standard conditions
• Enthalpy change of dissociation

  The enthalpy change when 1 mole of bonds of the same type of molecule in the gaseous state is broken
• Enthalpy change of atomisation

  The enthalpy change when 1 mole of gaseous atoms is made from an element in it’s standard state
• Enthalpy change of 1st ionisation

  The enthalpy change when 1 mole of a gaseous 1+ ions are made from 1 mole of gaseous atoms
• 1st Electron affinity

  The enthalpy change when 1 mole of gaseous 1- ions are made from 1 mole of gaseous atoms

  O (g) —-> O- (g)
• 2nd Electron affinity

  The enthalpy change when 1 mole of gaseous 2- ions are made from 1 mole of gaseous 1- ions
• 2nd Ionisation

  The enthalpy change when 1 mole of gaseous 2+ ions are made from 1 mole of gaseous 1+ ions
• enthalpy of hydration of an ion

  enthalpy change when 1 mole of a gaseous ion forms aqueous ions