Iodine has a low boiling point because of its weak intermolecular forces. Iodine molecules are held together by van der Waals forces, which are the weakest type of intermolecular force. These forces are easily overcome by the energy of heat, which is why iodine boils at a relatively low temperature.

In contrast, diamond has a very high boiling point because of its strong covalent bonds. Diamond is made up of carbon atoms that are covalently bonded to each other in a very rigid structure. These bonds are very strong and require a lot of energy to break, which is why diamond has such a high boiling point.

Here is a table summarising the key differences between iodine and diamond:

| Property | Iodine | Diamond |

|---|---|---|

| Boiling point | 184.3 °C | 3,550 °C |

| Intermolecular forces | van der Waals forces | Covalent bonds |

| Bond strength | Weak | Very strong |