Final answer:
Intermolecular forces in a compound are London Dispersion forces, dipole-dipole interactions, and hydrogen bonding, ranging from weakest to strongest in that order. These forces influence a substance's physical properties such as boiling and melting points.
Step-by-step explanation:
The types of intermolecular forces present in a compound include London Dispersion forces, dipole-dipole interactions, and hydrogen bonding. These forces are significant because they explain how molecules or atoms interact with each other in a substance, influencing properties such as boiling and melting points. London Dispersion forces are the weakest and are present in all molecules. Dipole-dipole interactions occur when there are areas of positive and negative charge within a molecule due to polar covalent bonds. The strongest of the three is hydrogen bonding, which occurs specifically when hydrogen is covalently bonded to nitrogen, oxygen, or fluorine.
In addition to these three main types, there are also ion-ion interactions responsible for ionic bonding, and ion-dipole interactions that occur when ionic substances dissolve in polar substances like water, often included in the collective term 'van der Waals forces.'