Answer:
The Born Haber cycles is an adaption of Hess’s law to calculate lattice enthalpy from other data
The lattice enthalpy cannot be determined directly. We calculate it indirectly by making use of changes
for which data are available and link them together in an enthalpy cycle the Born Haber cycle
Enthalpy of lattice formation
The Enthalpy of lattice formation is the standard enthalpy
change when 1 mole of an ionic crystal lattice is formed
from its constituent ions in gaseous form. Na+
(g) + Cl- (g) NaCl (s) [Latt H = -787 kJ mol-1
]
Enthalpy of lattice dissociation
The Enthalpy of lattice dissociation is the standard enthalpy
change when 1 mole of an ionic crystal lattice form is
separated into its constituent ions in gaseous form.
NaCl (s) Na+
(g) + Cl- (g) [Latt H = +787 kJ mol-1
]
Generally Lattice Enthalpy refers to the enthalpy change when a lattice is made from gaseous ions.
Some exam boards refer to the opposite process at tim
Explanation:
