Help lattice Enthalpy

Help I don’t get 1.2 and how to work it out the arrows are correct I copied them down from ms since I don’t understand and need help!!

(edited 1 year ago)

Reply 1

TypicalNerd

Original post by Alevelhelp.1

Help I don’t get 1.2 and how to work it out the arrows are correct I copied them down from ms since I don’t understand and need help!!

Think about the sizes and charges on the ions.

The smaller and the more charged the both anion and cation in the salt are, the more negative the lattice enthalpy of formation will be.

Barium is below magnesium in group 2, so it Ba^2+ is a bigger ion than Mg^2+.

The oxide ion is O^2-, so the magnitude of its charge is greater than that of Cl^-. It should also be noted that oxygen is on period 2 and chlorine is on period 3, so Cl^- is a bigger ion than O^2-.

Using this info, can you deduce which compound should have the most exothermic lattice enthalpy of formation?