enthalpy definitions

First ionisation energy

The energy required to remove 1 electron from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous 1+ ions under standard conditions: M_(g) → M⁺_(g) + e^-

Second Ionisation energy

the energy required to remove 1 electron from each 1⁺ ion in 1 mol of gaseous 1⁺ ions to form 1 mol of gaseous 2⁺ ions under standard conditions: M²⁺_(g) → M¹⁺_(g) + e^-

standard enthalpy change of atomisation

the enthalpy change when one mole of gaseous atoms is formed from the element under standard conditions. NOTE - formation of 1 mole of atoms

Electron Afiinity

First electron affinity: enthalpy change when 1 electron is added to each atom in 1 mole of gaseous atoms under standard conditions, to form 1 mole gaseous 1- ions

Lattice Enthalpy

the energy released when 1 mole of ionic compound is formed from its constituent gaseous ions under standard conditions (298K, 100KPa) : Na⁺_(g) + Cl^- _(g) → NaCl_(s)

Standard enthalpy change of formation

The energy released when 1 mole of ionic compound is formed from its elements under standard conditions (298K, 100kPa) with all reactants and products in their standard states. for NaCl : Na_(s) + ½ Cl_2(g) → NaCl_(s)

is second ionisation energy endothermic or exothermic?

endothermic

is standard enthalpy change of atomisation endo or exo

always endothermic

first electron affinity, endo or exo?

EXO

second electron affinity endo or exo

endothermic

enthalpy change of solution definition

the enthalpy change when 1 mol of solute is dissolved in water under standard conditions

enthalpy change of hydration definition

the enthalpy change when 1 mole of gaseous ions are completely surrounded by water molecules under standard conditions

is enthalpy change of hydration exo or endo

exothermic

is enthalpy change of solution exo or endo

may be exothermic or endothermic