definitions of enthalpies

Question 1

What is Enthalpy of Formation?

Answer 1

ΔH when one mole of a compound is formed from its elements under standard conditions, with all reactants and products in their standard states.

Question 2

What is 1st Ionisation Enthalpy?

Answer 2

ΔH when one mole of electrons is removed from one mole of gaseous atoms to form one mole of gaseous ions with a single positive charge.

Question 3

What is 1st Electron Affinity?

Answer 3

ΔH when one mole of gaseous atoms is converted into a mole of gaseous ions, each with a single negative charge

Question 4

What is Enthalpy of Atomisation?

Answer 4

ΔH when 1 mole of gaseous atoms is formed from an element in its standard state under standard conditions

Question 5

What is Lattice Formation Enthalpy?

Answer 5

ΔH when one mole of a solid ionic compound is formed from its gaseous ions under standard conditions

Question 6

What is Lattice Dissociation Enthalpy?

Answer 6

ΔH when one mole of a solid ionic compound is separated into its constituent ions under standard conditions.

Question 7

What is Enthalpy of Solution?

Answer 7

ΔH when one mole of an ionic substance dissolves in water to give a solution of infinite dilution under standard conditions.

Question 8

What is Enthalpy of Hydration?

Answer 8

ΔH when one mole of gaseous ions dissolve in sufficient water to give an infinitely dilute solution under standard conditions.

Question 9

What is Enthalpy of Combustion?

Answer 9

ΔH when 1 Mole of substance is completely combusted in oxygen under standard conditions.

Question 10

What is Mean Bond Enthalpy?

Answer 10

average energy required to break one mole of a specific type of covalent bond in the gas phase

averaged over a range of compounds.