An isotope of hydrogen commonly referred to as heavy water is​

Heavy water is a compound that is made up of oxygen and deuterium, a heavier isotope of hydrogen which is denoted by ‘ 2 H’ or ‘D’. Heavy water is also called deuterium oxide and is denoted by the chemical formula D 2 O.

Density: 1.107 g/mL

Dipole moment: 1.87 D

Heavy Water (Deuterium Oxide): D2O

Molecular Mass: 20.02 grams/mole

Explanation:

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.