What characteristic distinguishes semiconductors from conductors?

The characteristic that distinguishes semiconductors from conductors primarily revolves around the number of valence electrons. Semiconductors typically have four valence electrons, which positions them between conductors (which generally have one or more valence electrons that allow for free electron movement) and insulators (which have insufficient free electrons for conductivity).

In semiconductors, the arrangement of these four valence electrons forms covalent bonds in a crystal lattice, resulting in a material that can conduct electricity under certain conditions, such as when energy is supplied (for example, through heat or doping with impurities). This property allows semiconductors to be versatile components in electronic devices, as they can switch between conducting and non-conducting states depending on external influences.

While overall conductivity, resistance to electric flow, and physical state are relevant properties, they are not the primary characteristics that set semiconductors apart from conductors. Conductivity and resistance relate more to the material as a whole and how it behaves under specific conditions rather than the intrinsic atomic structure, hence they do not capture the defining aspect of the semiconductor's nature.