1.8 Thermodynamics

• entropy is the measure of disorder
• as temp increases, entropy increases

  • particles have more kinetic energy, move further apart - more disordered
• entropy = products - reactants
• a feasible reaction is where delta G is negative
• standard conditions of enthalpy are 298K and 100kPa
• lattice enthalpy of DISSOCIATION


  when 1 mole of an ionic lattice is separated into its constituent ions in a gaseous state under sc
• lattice enthalpy of FORMATION


  when 1 mole of an ionic compound is formed from its constituent ions in a gaseous state under sc
• enthalpy of atomisation 


  e.c for the formation of 1 mole of gaseous atoms under sc
• electron affinity

  e.c when 1 mole of gaseous atoms gain an electron under sc (become -ve)
• ionisation energy

  1 mole of electrons removed from 1 mole of gaseous atoms to form 1 mole of gaseous ions under sc
• enthalpy of hydration


  when 1 mole of gaseous ions is dissolved in water to form 1 mole of aq ions under sc