lattice enthalpy Flashcards
define lattice enthalpy
the enthalpy change when one mole of an ionic compound is converted to gaseous ions
example of lattice enthalpy
NaCl(s) -> Na+(g) + Cl-(g)
define enthlapy of atomisation
the enthalpy change when one mole of gaseous atoms are formed from the element in its standard state
define first electron affinity
enthalpy change when one mole of gaseous atoms is converted to gaseous ions with a single negative charge
define enthalpy of solution
the enthalpy change when one mole of a solute dissolves in water
define enthalpy of hydration
the enthalpy change when one mole of gaseous ions is converted to one mole of aqueous ions
example of enthalpy of atomisation
Na(s) -> Na(g). 1/2Cl2(g) ->Cl(g)
example of bond enthalpy
Cl2(g) -> 2Cl(g)
how is bond dissociation related to atomisation
bond dissociation is twice the enthalpy of atomisation for diatomic elements
example of first ionisation
Na(g) -> Na+(g) + e-
example of first electron affinity
Cl(g) + e- -> Cl-
define standard enthalpy of formation
enthalpy change when one mole of a compound is formed from its element under standard conditions
example of standard enthalpy of formation
Na(s) + 1/2Cl2 (g) -> NaCl(s)
example of enthalpy of hydration
Na+(g) -> Na+(aq)
how to calculate enthalpy of hydration
enthalpy of solution= lattice enthalpy + enthalpy of hydration
trends in lattice enthalpy
increase and so attractive forces between the ionsas charge on metal ion increases the lattice enthalpy increases
as the size of the ion increases the lattice enthalpy decreases ( with the bigger ions- the distance between the ions is less)
