The valence of hydrogen is 1). Valence is defined as the number of electrons that an atom can lose, gain, or share with another atom to form a chemical bond. Hydrogen has only one electron in its outermost shell, which makes it unique. It can bond with many elements by sharing its one electron with another atom to fill its energy levels. For example, hydrogen can bond with carbon to form methane or with nitrogen to form ammonia. The valence of hydrogen is important in determining the chemical properties of many compounds that contain hydrogen.