Question

Each hydrogen atom has one valence electron, but it needs two electrons to be stable. How can both hydrogen atoms each achieve a stable configuration?

Answer 1

Hydrogen atoms achieve a stable configuration by sharing their electrons through a covalent bond. In a molecule of hydrogen (H₂), two hydrogen atoms come together and each contributes one electron to form a shared electron pair. This shared pair of electrons allows both hydrogen atoms to have access to two electrons, which fulfills the "octet rule" for stability in this case, as having two electrons allows each hydrogen atom to achieve a full outer shell similar to helium, which is a noble gas. This mutual sharing of electrons is what helps the hydrogen atoms reach a stable electronic configuration.