Chemistry · S and p Block Elements

Melting and boiling points generally increase with the number of electrons, because more electrons lead to stronger London dispersion (van der Waals) forces, resulting in higher melting/boiling points.

This option is correct because the number of electrons contributes to the strength of intermolecular forces, such as London dispersion forces, which increase with more electrons, leading to higher melting and boiling points.

Incorrect. The number of neutrons does not directly affect melting and boiling points as they do not participate in chemical bonding or influence intermolecular forces.

Incorrect. While paired electrons are stable, it is the unpaired electrons that significantly influence the strength of the forces between atoms or molecules, thereby affecting melting and boiling points.

Incorrect. The number of protons determines the atomic number and identity of an element, but does not directly influence the melting and boiling points of substances.