atomic mass unit (u, dalton)

atomic mass unit (u, dalton)

The masses of atoms and molecules are generally given in atomic mass units. These units are based on a scale in which the mass of carbon 12 is taken to be 12. Atomic masses were originally given as atomic weights on a scale where the mass of the hydrogen atom was unity, later they were based on oxygen or oxygen 16; these scales have all been replaced by the carbon 12 scale.

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Industry/Domain: Astronomy
Category: General astronomy
Company: Caltech
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