AS 2.8: Energetics Flashcards
Endothermic Reaction
A reaction in which the enthalpy of the product is greater than the enthalpy of reactants (Heat is absorbed).
Exothermic Reaction
A reaction in which the enthalpy of the products is less than the enthalpy of the reactants (Heat is liberated).
Standard Conditions
298K and 100kPa (1 atmosphere).
Standard Enthalpy Change
The change in heat pressure at constant pressure, measured under standard conditions.
Enthalpy of Reaction
The enthalpy change when the mole quantities of reactants as stated in the balanced equation react together under standard conditions.
Standard Enthalpy of Combustion
The enthalpy change when one mole of a substance is completely burnt in oxygen under standard conditions.
Standard Enthalpy of Formulation
The enthalpy change when one mole of a compound is formed from its elements under standard conditions.
Standard Enthalpy of Neutralisation
The enthalpy change when one mole of a compound is produced in a neutralisation reaction under standard conditions and having a concentration of 1 mol dm⁻³
Specific Heat Capacity
The amount of heat required to raise the temperature of of 1g of a substance by 1K.
Conservation of Energy
Energy cannot be created or destroyed, only converted from one form to another.
Hess’s Law
The total enthalpy change for a reaction is independent of the route taken, provided that initial and final conditions are the same.
Average Bond Enthalpy
This is the energy required to break one mole of a given bond averaged over many compounds
