3.2.1 Enthalpy Changes Flashcards
1
Q
Standard enthalpy of combustion
A
Enthalpy change when one mole of a substance
Is completely burned in excess oxygen
Under standard conditions of 298K and 100kPa
2
Q
Standard enthalpy of formation
A
The enthalpy change when one mole of a substance
Is formed from its elements in their standard states
Under standard conditions of 208K and 100kPa
3
Q
Standard enthalpy change of neutralisation
A
The enthalpy change of one mole of H2O
Is formed from the reaction of an acid with a base
Under standard conditions of 298K and 100kPa
4
Q
Why are bond enthalpies described as average enthalpies.
A
Each individual bond will be in a different environment and therefore have a different strength
5
Q
Average bond enthalpy
A
The breaking of 1 mole of bonds in gaseous molecules
