Born-Haber Cycles - for OCR A Level Chemistry

This video takes you through an essential and a more complex Born Haber cycle.
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As mentioned, here is an explanation of the enthalpy change signs for some of these reactions ...
Atomisation = always endothermic because it requires breaking bonds (which requires energy) to form gaseous atoms.
Ionisation energy = always endothermic because energy is required to break the attraction between the nucleus and the outer electron(s). This is also true of second ionisation energy and in fact you would notice these values be MORE endothermic as trying to remove an electron from an already positive ion requires more energy (fewer electrons in the shells attracted by the original number of protons in the nucleus).
1st Electron affinity = always exothermic because there is a net attraction between the non metal element and the extra electron (the anion formed is more stable).
2nd Electron affinity = always endothermic because your reactants are an electron (negative) and an anion (negative too) and these repel each other - so reacting them requires energy.
Lattice Enthalpy = always exothemric as it represents forming ionic bonds starting from gaseous ions. The solid lattice formed has less energy (is more stable).
* Careful AQA people seeing this video as you learn lattice enthalpies for two directions and may have 2 different definitions. Sorry not sorry.