Choose the compound that should have the LOWEST lattice energy according to the ionic bonding model.

Question

Group of answer choices

(a) SrCl₂

(b) SrI₂

(c) MgF₂

(d) MgI₂

(e) MgCl₂

Answer 1

All have 2+ cation and 1- anion, so we look at atomic radii next.

Sr2+ is larger than Mg2+ so according to Coulomb's law, the attraction to the anion will be less.

Comparing SrCl₂ to SrI₂, I^- is larger than Cl^- so the lowest lattice energy would be SrI₂