What is the unified atomic mass unit (u)?
The atomic mass constant is u = 1.66053906660e-27 kg (uncertainty ±5.0e-37). In energy units it is 931.49410242 MeV/c^2.
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| Value | 1.66053906660e-27 kg |
|---|---|
| Symbol | u (Da) |
| Energy equivalent | 931.49410242 MeV/c^2 |
| Uncertainty | ±5.0e-37 kg |
| Source | CODATA 2018 |
Frequently asked questions
What is 1 atomic mass unit in kg?
1 u = 1.66053906660e-27 kg, defined as 1/12 the mass of a carbon-12 atom.
What is 1 u in MeV?
In energy units, 1 u = 931.49410242 MeV/c^2.
Is the atomic mass unit the same as the dalton?
Yes. The unified atomic mass unit (u) and the dalton (Da) are identical units.
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