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How are hydrogen and deuterium related as isotopes?

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Bohr model diagram of a hydrogen atom showing a green nucleus labeled H, a single electron orbit, and text with atomic mass 1.008 and electron configuration 1. — atom The Bohr model describes the structure of atoms, in this case hydrogen.

Hydrogen and deuterium are related as isotopes of the same element, hydrogen. While an ordinary hydrogen atom consists of a nucleus containing a single proton, a deuterium atom contains one proton and one neutron in its nucleus.12

Because of this additional neutron, deuterium has approximately double the mass of ordinary hydrogen. Although they participate in the same types of chemical reactions, deuterium typically reacts more slowly than ordinary hydrogen. This difference in reaction rates, known as a kinetic-isotope effect, allows deuterium to be used effectively as an isotopic tracer in scientific research. Additionally, while ordinary hydrogen is the most abundant form, deuterium is a stable species found in natural hydrogen compounds in small concentrations.132