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Periodic table
›
hydrogen
›
H-1
Hydrogen-1 (H-1)
Identity
Protons
1
Neutrons
0
Mass number
1
Mass
1.007825 ± 0.000014 u
Mass excess
7.289 MeV
Spin
1/2+*
Stability
stable
Natural occurrence
99.99 %
of hydrogen
All isotopes of hydrogen