Enthalpy and Entropy

Lattice enthalpy

the formation of one mole of an ionic compound from its gaseous ions

Enthalpy Change of Solution

The enthalpy change due to 1 mole of a solute dissolving in a solvent.

Enthalpy change of hydration

The enthalpy change due to dissolving gaseous ions in water to form 1 mole of aqueous ions.

Standard enthalpy change of formation

the enthalpy change due to 1 mole of a compound forming from its constituent elements under standard conditions.

Standard enthalpy change of atomisation

the enthalpy change by forming of 1 mole of gaseous atoms from the element in its standard state under standard conditions.

First ionisation energy

The enthalpy change required to remove one electron from each atom in 1 mole of gaseous atoms to form one mole of +1 gaseous ions.

First electron affinity

The enthalpy change when an electron is added to each atom in 1 mole of gaseous atoms to form one mole of –1 gaseous ions.

Standard entropy (S^o)

The entropy of one mole of a substance under standard conditions (100 kPa and 298 K).