chemical energetics

enthalpy change of atomisation

• 
  

• enthalpy chnage when 1 mole of gasous atoms is frmed from its elements under standard conditions

• endothermic

lattice energy definition

• energy change

• when 1 mole of ionic compound is formed

• from its gaseous ions

• under standard conditions

• endothermic

first electron affinity

• energy change

• when 1 mole of electrons is added

• to 1 mole of gasous ions

• to form 1 mole of 1+ ions

• under stndard condition

• exothermic

second electron affinity

• enthallpy change when 1 mole of electrons is added to 1- gasous ions to form 1 mole of 2- gasous ions.

• endothermic reaction

factors affecting lattice energy

• charge on ion, greater larger lattice

• size of ion, smaller is more lattice

lattice energy trend

• increases across the period

• decreases down the group

electron affinity trend

• increases across the period

• decreases down the group