Which has higher lattice energy: MgO or LiF ?
A compound has higher lattice energy if it's ions have smaller size and greater charge
- Li cation is smaller than Mg cation => +1 for (LiF)
- Fluoride anion is smaller than oxide anion => +1 for (LiF)
- Mg cation has greater charge than Li cation => +1 for (MgO)
- Oxide anion has greater charge than fluoride anion => +1 for (MgO)
Therefore, 'charge' factor favour MgO while 'size' factor favour LiF.
So, which one will have higher lattice energy?