8.4: Hydrogen
- Page ID
- 151402
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Hydrogen Isotopes
Elemental hydrogen exists primarily as the hydrogen-1 isotope, although hydrogen-2 and hydrogen-3 are also known. Some properties of these isotopes are given in Table \(\sf{\PageIndex{1}}\).
Table \(\sf{\PageIndex{1}}\). Atomic properties of hydrogen isotopes. Adapted slightly from https://chem.libretexts.org/Bookshelves/General_Chemistry/Book%3A_Chemistry_(Averill_and_Eldredge)/21%3A_Periodic_Trends_and_the_s-Block_Elements/21.2%3A_The_Chemistry_of_Hydrogen
| Protium | Deuterium | Tritium | |
|---|---|---|---|
| symbol | \(\sf{^1_1H}\) | \(\sf{^2_1H}\) or D | \(\sf{^3_1H}\) or T |
| neutrons | 0 | 1 | 2 |
| mass (amu) | 1.00783 | 2.0140 | 3.01605 |
| abundance (%) | 99.9885 | 0.0115 | ~10−17 |
| half-life (years) | — | — | 12.32 |
| boiling point of X2 (K) | 20.28 | 23.67 | 25 |
| melting point/boiling point of X2O (°C) | 0.0/100.0 | 3.8/101.4 | 4.5/? |
| Notable features | NMR active with a spin of \(\sf{1/2}\) | NMR active with a spin of \(\sf{1}\) |
Contributors and Attributions
Stephen Contakes, Westmont College