5.2.1 lattice enthalpy

Question 1

define standard enthalpy change of electron affinity

Answer 1

when one mole of electrons is added to one mole of gaseous atoms/ions
–> first ea usually exothermic as energy required to overcome e- repulsion less than the energy released when the nucleus attracts the e-

Question 1

define standard enthalpy change of atomisation

Answer 1

enthalpy change when 1 mole of gaseous atoms are formed from the element in its standard state, under standard conditions. e.g. 1/2 Cl2 (g) -> Cl (g)
is endothermic bc require energy

Question 2

define lattice enthalpy

Answer 2

formation of 1 mol of ionic lattice from gaseous ions

Question 3

enthalpy change of solution

Answer 3

dissolving of 1 mol of solute

Question 4

enthalpy change of hydration

Answer 4

dissolving of 1 mol of gaseous ions in water

Question 5

what affects the exothermicness of the enthalpy change of hydration and lattice enthalpy

Answer 5

ionic radius and ionic charge
higher charge density forms stronger ionic bonds within lattice and stronger ion-dipole bonds in aqueous solutiuon.