Energetics

why is x less exothermic than y?

x has a lower charge to size ratio, so it forms weaker bonds

why is there a difference between the theoretical and actual formation enthalpy recorded

there is covalent character

why is there little difference between the theoretical and actual values of enthalpy formation

it is almost perfectly ionic

why is (gas) higher in entropy than (solid)

gases are more disordered than solids

gibbs free energy

ΔG = ΔH - TΔS

why is formation enthalpy a different value to bond enthalpy

mean bond enthalpies are not exact as they are averaged from multiple reactions, enthalpy of formation more accurate

why is 2nd EA endothermic?

the negative ion and the electron have repulsion so it requires energy to add the second electron

why is 2nd IE more exothermic

e- nearer nucleus so it takes more energy to remove the e- from a positive species as they are strongly attached

affect of catalyst on yield

no change in yield as increases rate of forward and backward reaction equally