Table 1 shows the melting points of three substances.
SubstanceMelting point / KAluminium oxide (Al2O3)2345Iodine (I2)387Hydrogen iodide (HI)222 \begin{array}{|l|c|} \hline \textbf{Substance} & \textbf{Melting point / K} \\ \hline \text{Aluminium oxide (Al}_2\text{O}_3\text{)} & 2345 \\ \hline \text{Iodine (I}_2\text{)} & 387 \\ \hline \text{Hydrogen iodide (HI)} & 222 \\ \hline \end{array} SubstanceAluminium oxide (Al2O3)Iodine (I2)Hydrogen iodide (HI)Melting point / K2345387222Explain why the melting points of these substances are different.
You should refer to the structure of and bonding in each substance.
54 exam-style questions on AQA A Level Chemistry Bonding, covering Ionic bonding, Nature of covalent and dative covalent bonds, Metallic bonding, Bonding and physical properties, Shapes of simple molecules and ions, Bond polarity, and Forces between molecules. Each one has a worked solution and a mark scheme showing where the marks go.