How do intermolecular forces affect the properties of substances?

Intermolecular forces play a crucial role in determining various physical properties of substances, such as boiling and melting points, solubility, and volatility. These forces arise from interactions between molecules and can vary significantly in strength, affecting how closely molecules are held together, which in turn influences the properties mentioned.

For example, strong intermolecular forces, such as hydrogen bonding, can lead to higher boiling points and melting points because more energy is required to overcome these forces during phase changes. Substances with weak intermolecular forces tend to have lower boiling and melting points.

Additionally, solubility is significantly influenced by intermolecular forces. A substance will dissolve well in a solvent if the intermolecular forces between the solvent and solute molecules are comparable in strength to those holding the solute together. Lastly, volatility, which describes how readily a substance vaporizes, is also affected; substances with weaker intermolecular forces generally have higher volatility because they require less energy to escape into the vapor phase.

The other options do not accurately reflect the role of intermolecular forces. The atomic number is determined by the number of protons in the nucleus and is not influenced by intermolecular forces. While intermolecular forces can indeed influence physical states (as related to boiling and melting points),