Enthalpy A2

Lattice enthalpy

The enthalpy change that accompanies the formation of one mole of an ionic compound to form one mole of an ionic compound from its gaseous ions under under standard conditions

First ionisation enthalpy

The enthalpy change that takes place when one electron is removed from each atom in one mole of gaseous atoms, to form one mole of gaseous 1+ ions

Enthalpy change of atomisation

The enthalpy change that takes place when one mole of gaseous atoms form from the elements, in their standard states

First electron affinity

The enthalpy change that takes place when one electron is added to each atom in one mole of gaseous atoms, to form one mole of gaseous 1- ions.

Enthalpy change of formation

The enthalpy change that takes place when one mole of a compound is formed from its constituent elements, in their standard states, under standard conditions

Enthalpy change of solution

The enthalpy change that takes place when one mole of a compound is completely dissolved in water, under standard conditions

Enthalpy change of hydration

The enthalpy change that takes place when one mole of isolated gaseous ions is dissolved in water, forming one mole of aqueous ions, under standard conditions

Is electron affinity positive or negative?

First = negative (exothermic)

Second = positive (endothermic)