Born Haber cycle helps to determine lattice enthalpy of ionic compound as well as electron gain enthalpy of different elements. Based on the diagram drawn, answer the questions given below.

What is the lattice enthalpy for the formation of `MgCI_(2)`?

Options

A. `-20kJ`
B. `-40kJ`
C. `-15kJ`
D. `+40kJ`

Answer

A

Explanation

`{:(Mg^(2+)(g)+2CI^(-)(g)rarrMgCI_(2)(s),DeltaH_(L.E)=?),(CI_(2)(g)rarr2CI(g),[30-5=25]),(2CI(g)rarr2CI^(-)(g),[10-30=-20]),(Mg(g)rarrMg^(+)(g),[135-10=25]),(Mg^(+)(g)rarrMg^(2+)(g),[40-35=5]),(Mg(s)+CI_(2)(g)rarrMgCI_(2)(s),[20-0=20]),(Mg(s)rarrMg(s),[5-0=5]):}`