5.2.1 lattice enthalpy

lattice enthalpy

the enthalpy change due to the formation of 1 mol of ionic lattice from gaseous ions

the enthalpy changes that takes place for the formation of one mole of gaseous atoms from the element in its standard state under standard conditions

enthalpy of atomisation

the standard enthalpy of formation of a substance is the enthalpy change that occurs when 1 mole of the substance is formed from its constituent elements in their standard states.

enthalpy of formation

the enthalpy change that takes place when one electron is added to each atom in one mole of gaseous atoms to form one more of gaseous 1- ions(always exothermic)

first electron affinity

first ionisation energy

the enthalpy change required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions

factors affecting lattice enthalpy
ionic size
-ionic radius increases
-attraction between ions ___
-lattice enthalpy is less _____
-melting point ____

decreases, negative, decreases

factors affecting lattice enthalpy
ionic charge
-ionic charge increases
-attraction between ions ____
-lattice energy becomes more ____
-melting point _____

increases, neagative, increases

enthalpy change of solution

the enthalpy change that takes place when one mole of a solute dissolves in a solvent

the enthalpy change when separate ions interact with polar water molecules to form hydrated aqueous ions

enthalpy change of hydration

factors affecting hydration enthalpy
ionic size
-ionic radius increases
-attraction between ion and water molecules
-hydration energy is less _

increases, negative

factors affecting hydration enthalpy
ionic charge
-ionic charge increases
-attraction with water molecules ____
-hydration energy becomes more _____

increases, negative

entlapy of formation

product-reactants

lattice entlapy=

formation-(everything)

enthlapy of solution=

-lattice enthlapy+(change of hydration)

solubility
if the hydration enthalpies lattice enthalpy, the overall enthalpy change will be ___ so the compound so dissolve

more exothermic