Chemistry - PERIODIC TABLE Question with Solution | TestHub

Question Explanation:

Identifying the incorrect thermodynamic statement about lattice energy.

Concepts : Energetics of solubility, Born-Landé factors.

Solution:

1.  For the same ions, lattice energy is generally higher for a structure with higher coordination number if other factors remain constant.

This is  correct .

2.  The Born exponent  n  depends on electronic configuration and repulsion. For noble gas configuration, its value is related to the type of ions, and it generally increases with larger electron cloud size.

This is taken as  correct  in standard approximation.

3.  MgO is stable because the very high lattice energy compensates for the highly endothermic second electron gain enthalpy of oxygen.

This is  correct .

4.  Enthalpy of solution:

ΔHₛₒₗₙ = Hydration Enthalpy + Lattice Enthalpy

If lattice energy magnitude is greater than hydration enthalpy magnitude, then dissolution will  not  be exothermic; it will tend to be  endothermic .

So this statement is  incorrect .