Enthalpy Definitions

Question 1

Lattice Formation Enthalpy

Answer 1

The enthalpy change when 1 mole of a solid ionic compound is formed from its gaseous ions.

Question 2

Lattice Dissociation Enthalpy

Answer 2

The enthalpy change when 1 mole of a solid ionic compound is completely dissociated into its gaseous ions.

Question 3

Enthalpy Change of Formation

Answer 3

The enthalpy change when 1 mole of a compound is formed from its elements in their standard states.

Question 4

Bond Dissociation Enthalpy

Answer 4

The enthalpy change when all the bonds of the same type in 1 mole of gaseous molecules are broken.

Question 5

Enthalpy Change of Atomisation of an Element

Answer 5

The enthalpy change when 1 mole of gaseous atoms is formed from an element in its standard state.

Question 6

Enthalpy Change of Atomisation of a Compound

Answer 6

The enthalpy change when 1 mole of a compound in its standard state is converted to gaseous atoms.

Question 7

First Ionisation Energy

Answer 7

The enthalpy change when 1 mole of gaseous 1+ ions are formed from 1 mole of gaseous atoms.

Question 8

Second Ionisation Energy

Answer 8

The enthalpy change when 1 mole of gaseous 2+ ions are formed from 1 mole of gaseous 1+ ions.

Question 9

First Electron Affinity

Answer 9

The enthalpy change when 1 mole of gaseous 1- ions are formed from 1 mole of gaseous atoms.

Question 10

Second Electron Affinity

Answer 10

The enthalpy change when 1 mole of gaseous 2- ions are formed from 1 mole of gaseous 1- ions.

Question 11

Enthalpy Change of Hydration

Answer 11

The enthalpy change when 1 mole of aqueous ions is formed from gaseous ions.

Question 12

Enthalpy Change of Solution

Answer 12

The enthalpy change when 1 mole of an ionic substance dissolves in enough solvent to form an infinitely dilute solution.