One takes into account the percentage and atomic masses of protium and deuterium.
Hydrogen is a non meta element. Atomic mass of it is 2.
The atomic weight (not mass) of hydrogen is [1,00784; 1,00811] or in an abridged form 1,008.
Hydrogen
The atomic mass of the most common form of hydrogen is 1. There are isotopes of hydrogen with a mass of 2 (deuterium) and 3 (tritium), but they are rare.
The reduced mass of deuterium is approximately 1.67 atomic mass units. It is calculated as the product of the atomic mass of deuterium and the atomic mass of hydrogen, divided by their sum.
The atomic weight of hydrogen is 1,007 94 ± 0,000 07 atomic units of mass.
atomic mass for hydrogen is 1.00794.
The atomic mass of water (H2O) is calculated by adding the atomic masses of its constituent elements, which are hydrogen (H) and oxygen (O). The atomic mass of hydrogen is approximately 1, and the atomic mass of oxygen is approximately 16. Therefore, the atomic mass of water is approximately 18 (1 + 1 + 16).
The average atomic mass of Barium is 137.33 amu.
The atomic mass of hydrogen is 1u. Atomic mass of bromine is 80u. Therefore, the molar mass of hydrogen bromide is 1+80=81u.
The relative atomic mass of hydrogen peroxide, H2O2, is approximately 34.01 g/mol. This value is calculated by adding the atomic masses of the elements in the molecule (2 hydrogen atoms and 2 oxygen atoms).
The 'standard' hydrogen atom has atomic number 1, atomic mass 1, no neutrons. Although there are 2 other isotopes of hydrogen: - (cant confirm name) which has atomic mass 2 and 1 neutron. - (cant confirm name) has atomic mass of 3 and 1 neutron. All isotopes have atomic number 1.