Normally, a carbon atom shares all four of its valence electrons to create four bonds with other atoms (tetravalent carbon).

The distribution of outermost shell electrons, known as valence electrons, of organic molecules was experimentally observed for the first time by a team led by Nagoya University in Japan.

The “lead” of a pencil is actually made of a substance called graphite which is made of carbon atoms. The picture shows a close-up of one carbon atom. A hydrogen atom has one proton as the nucleus and ...