Constants & Units · constant
Bohr radius
a₀ = 5.291 772 105 44(82) × 10⁻¹¹ m
- Unit
- m
- Value
- 5.291 772 105 44(82) × 10⁻¹¹
- Exact
- no
- Note
- The size of a hydrogen atom in its ground state — the natural ruler of chemistry.
- Symbol
- a₀
- Category
- Atomic & nuclear
- Numeric
- 5.29177210544e-11
- Uncertainty
- ±1.6 × 10⁻¹⁰ relative
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