Enthalpy

Question 1

Enthalpy change of reaction

Answer 1

The enthalpy change associated with a stated reaction. Quantites of substances in standard states react completely under standard conditions

Question 2

Enthalpy change of formation

Answer 2

The enthalpy change when one mole of a substance is produced from its elements in their standard states under standard conditions

Question 3

Enthalpy change of combustion

Answer 3

The enthalpy change when one mole of a substance is burned completely in oxygen under standard conditions

Question 4

Enthalpy change of neutralisation

Answer 4

The enthalpy change when solutions of acid and alkali react together under standard conditions to produce one mole of water

Question 5

Specific heat capacity

Answer 5

The energy required to raise 1g of substance by 1K without a change of state

Question 6

Bond enthalpy

Answer 6

The energy required to break one mole of the stated bond in a gaseous state, under standard conditions

Question 7

Hess’s law

Answer 7

Energy in reaction system must be conserved. Therefore the oberall enthalpy change is the same regardless of the route taken