Chemistry 3.6 - Enthalpy Changes - DEFINITIONS 0.0 / 5 ? ChemistryEnthalpyA2/A-levelWJEC Created by: Tashaleese_99Created on: 21-04-17 10:20 Enthalpy A heat change under constant pressure. 1 of 11 Hess's Law The total enthalpy change of a reaction will always be the same no matter what route is taken. 2 of 11 Standard enthalpy of atomisation The enthalpy change when one mole of gaseous atoms is formed from an element in its standard state. 3 of 11 Standard enthalpy of formation The enthalpy change when one mole of a compound is formed from its elements in their standard states under standard conditions. 4 of 11 First ionisation enthalpy The enthalpy change when one mole of gaseous +1 ions is formed from one mole of gaseous atoms. 5 of 11 First electron affinity The enthalpy change when one mole of gaseous -1 ions is formed from one mole of gaseous atoms. 6 of 11 Second electron affinity The enthalpy change when one mole of gaseous -2 ions is formed from one mole of gaseous -1 ions. THIS IS ALWAYS ENDOTHERMIC. 7 of 11 Enthalpy of hydration The enthalpy change when one mole of aqueous ions is formed from one mole of gaseous ions. 8 of 11 Enthalpy of solution The enthalpy change when 1 mole of a substance dissolves completely in a solvent. 9 of 11 Enthalpy of lattice breaking The enthalpy change when 1 mole of an ionic compound is broken up into gaseous ions. 10 of 11 Enthalpy of lattice formation The standard enthalpy change when one mole of a solid ionic compound is formed from its gaseous ions. 11 of 11
Comments
No comments have yet been made