Explain Born-Haber cycle for the fomation of 1 mole of sodium chloride crystal.

Explanation

Step 1 : Sublimation of metallic sodium of gaseous sodium atom with enthalpy sublimation `=DeltaH_(s)`
`Na(s) overset("sub lim ation")to Na(g), Delta= Delta H_(s)`
Step : 1 Dissociation of molecules to chlorine atoms with enthaply of dissociation =
`DeltaH_(d)(1)/(2)Cl_(2) (g) overset("Dissociation") to Cl(g), DeltaH=DeltaH_(4)`
Step-3 : Ionization of gaseous sodium with entahlpy of ionization `=DeltaH_(1)`
`Na(g)overset("Ionization")to Na^(+)(g)`
Step-4 : Addition of electron to gaseson chlorine atom with enthaply of electron affinity `Delta H_(Ed)Cl_((g))+e^(-)overset("Addition")toCl^(-)(g), DeltaH=DeltaH_(Ea)`
Step -5 Close packing of gaseous sodium ion and chloride ion the form lattice structure of NaCl, with lattice chloride ion to form lattice structure of NaCl, Lattice energy `U,NaCl^(+)(g)+Cl^(-)(g) to NaClDelta, Delta H=U`
Step -6 But sum of all the energies will be equal to the heat of formation of one mole of sodium chloride form its reluctant i.e., `DeltaH_(f)`
`Na(s)+(1)/(2)Cl_(2)(g) to NaCl(s), DeltaH=Deltaf_(f)`