Melting Point Trend (AQA A-Level Chemistry): Flashcards

Giant ionic or giant covalent structures

Giant ionic

$\text{Mg}^{2+}$ has higher charge density

Covalent character from $\text{Al}^{3+}$ polarising $\text{O}^{2-}$

Giant covalent

Strong covalent bonds throughout 3D lattice

Simple molecular

Weak intermolecular forces (van der Waals, dipole-dipole)

Larger size/mass gives stronger van der Waals forces

Weak van der Waals forces in small molecular structure