Lattice Enthalpy

• Lattice enthalpy is the enthalpy change that accompanies the formation of one mol of an ionic compound from its gaseous ions under standard conditions
• lattice enthalpy is from gaseous ions to ionic lattice compound
• lattice enthaply is exothermic so enthalpy change is negative and arrow points down on the born-haber cycle
• LE cannot be measured directly and so has to be calculated indirectly from known energy changes in an energy cycle
• the enthalpy change of formation is exothermic
• lattice enthalpy is exothermic
• when its exothermic, enthalpy change is negative and the arrow on cycle points down