01Four kinds
Ionic: high mp, brittle. Molecular: low mp, held by IMFs. Covalent network (diamond, SiO₂): very high mp, extremely hard. Metallic: conductive, malleable.
Particulate diagrams on the exam ask you to identify which kind from the arrangement.
02Notebook box
Network covalent > ionic > metallic (varies) > molecular for mp, roughly.
Worked example: SiO₂ melts at 1700 °C, CO₂ sublimes at −78 °C. Why? SiO₂ is a covalent network; CO₂ molecules only have LDFs.