Energetics

DEFINITIONS:

Standard enthalpy change of reaction: Enthalpy change when molar quantities of reactants, as stated in the balanced stoichiometric equation, react together.

Standard enthalpy change of neutralisation: Enthalpy change when one mole of water is formed during the neutralisation between an acid and a base under standard conditions of 1atm and 298k.

Standard enthalpy change of formation: Enthalpy change when one mole of a pure compound is formed from its constituent elements in their standard states under standard conditions of 1 atm and 298k.

Standard enthalpy change of combustion: Enthalpy change when one mole of a substance is completely burnt in excess oxygen under standard conditions of 1atm and 298k.

Standard enthalpy change of atomisation: Enthalpy change when one mole of separate gaseous atoms are produced from the element in its standard state under standard conditions of 1 atm and 298k.

Standard enthalpy change of hydration: Enthalpy change when 1 mole of free gaseous ions is surrounded by water molecules and form a solution at infinite dilution, under standard conditions of 1atm and 298k.

Standard enthalpy change of solution: Enthalpy change when 1 mole of solute is completely dissolved in a solvent to form an infinitely dilute solution under standard conditions of 1 atm and 298k.

Bond dissociation energy: Energy required to break one mole of covalent bonds between 2 atoms in the gaseous state.

First ionisation energy: minimum energy required to remove one mole of electrons from one mole of gaseous atoms producing one mole of gaseous singly charged positive ions.

Electron affinity: Enthalpy change when one mole of gaseous atoms or negatively charged ion gain one mole of electrons.

Lattice energy: Enthalpy change when 1 mole of an ionic crystalline solid is formed from its separate gaseous ions under standard conditions of 1atm and 298k.