poids atomique

Traductions

• anglais

  Date : 1986

  Définition

  The atomic weight of an element, which may in nature exist as a mixture of isotropes of different atomic mass, is the ratio of the statistical average weight of the atoms of the element (ie allowing for the differing natural abundances of the isotopes), to one twelfth of the weight of one atom of carbon-12.

  Note :

  Originally atomic weights were measured relative to the weight of one atom of hydrogen-1: the carbon-12 scale (which leads to very similar numbers for atomic weights), was chosen for ease of experimental determination.

  Terme :

  1. atomic weight