The picture shows a close-up of one carbon atom. A hydrogen atom has one proton as the nucleus and one electron in the region outside the nucleus. The electron and proton are attracted to each other.

As you move down a group in the periodic table, the covalent radius increases. Atoms increase in size. This is because of the screening effect of the filled inner electron levels. These electrons ...

Because excitons are electrically neutral, they remain unaffected by the periodic electric field, making them an ideal probe for studying electron dynamics. By adjusting the electric voltage ...

The ions formed have a full outer electron shell, so are very stable. See the study guide on groups in the periodic table for more information.