Constants library

Atomic Mass of Hydrogen measured

A_{\mathrm{r}}(\mathrm{H}) = 0.001008\ \text{kg/mol}

kg/molThe standard atomic weight of hydrogen, 1.0080 g/mol — the lightest entry on the periodic table and the anchor of the original mass scale.

A_{\mathrm{r}}(\mathrm{C}) = 0.012011\ \text{kg/mol}

kg/molThe standard atomic weight of carbon, 12.011 g/mol — the element that anchored the atomic mass scale from 1961 until the 2019 redefinition.

A_{\mathrm{r}}(\mathrm{N}) = 0.014007\ \text{kg/mol}

kg/molThe standard atomic weight of nitrogen, 14.007 g/mol — the divisor behind every fertiliser grade and every mg/L as N in a water report.

A_{\mathrm{r}}(\mathrm{O}) = 0.015999\ \text{kg/mol}

kg/molThe standard atomic weight of oxygen, 15.999 g/mol — the reference element for chemical atomic masses from Berzelius until 1961.

A_{\mathrm{r}}(\mathrm{Na}) = 0.02298976928\ \text{kg/mol}

kg/molThe standard atomic weight of sodium, 22.98976928 g/mol — a mononuclidic element, so the value is known to eleven significant figures.

A_{\mathrm{r}}(\mathrm{Cl}) = 0.03545\ \text{kg/mol}

kg/molThe standard atomic weight of chlorine, 35.45 g/mol — the textbook example of a fractional atomic weight produced by isotope mixing.

A_{\mathrm{r}}(\mathrm{Ca}) = 0.040078\ \text{kg/mol}

kg/molThe standard atomic weight of calcium, 40.078 g/mol — the ion that dominates water hardness and the scale it leaves behind.

A_{\mathrm{r}}(\mathrm{Fe}) = 0.055845\ \text{kg/mol}

kg/molThe standard atomic weight of iron, 55.845 g/mol — the element with the highest binding energy per nucleon, where fusion stops paying.

A_{\mathrm{r}}(\mathrm{S}) = 0.03206\ \text{kg/mol}

kg/molThe standard atomic weight of sulfur, 32.06 g/mol — the divisor for sulfate, sulfuric acid and every fuel sulfur specification.