Lattice Enthalpy - Born-Haber Cycles
Lattice enthalpy is a measure of ionic bond strength. Born Haber Cycles are used to calculate
this.
Atomisation of metal ion.
Atomisation of other ion.
First ionisation of metal ion until ion is made.
First electron affinity of other ion or second until ion is made.
All taken away from each other = lattice enthalpy of formation
up - energy is going into the system
down - energy leaving the system
if the metal ion has more than one charge add the extra ionisation energies and electron
affinities to get the ion
second ionisation energy would be double the first ionisation energy
Factors that affect the lattice enthalpy:
Size of Ion (smaller = larger)
As the ionic radius of ions increases the lattice enthalpy becomes less exothermic.
The charge on the ions is more spread out when the ions are larger. This causes the
electrostatic force to be weaker due to ions being further apart.
Charge on Ion (larger = larger)
Lattice enthalpy is a measure of ionic bond strength. Born Haber Cycles are used to calculate
this.
Atomisation of metal ion.
Atomisation of other ion.
First ionisation of metal ion until ion is made.
First electron affinity of other ion or second until ion is made.
All taken away from each other = lattice enthalpy of formation
up - energy is going into the system
down - energy leaving the system
if the metal ion has more than one charge add the extra ionisation energies and electron
affinities to get the ion
second ionisation energy would be double the first ionisation energy
Factors that affect the lattice enthalpy:
Size of Ion (smaller = larger)
As the ionic radius of ions increases the lattice enthalpy becomes less exothermic.
The charge on the ions is more spread out when the ions are larger. This causes the
electrostatic force to be weaker due to ions being further apart.
Charge on Ion (larger = larger)
