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Unit of mass

The dalton (symbol Da) is the immediate predecessor of the atomic mass unit. It is named after John Dalton in recognition of his achievement in introducing the atomic hypothesis into chemistry. Whereas the unified atomic mass unit is defined as 1/12 of the mass of a single atom of 12C, the dalton was defined as 1/16 of the mass of an atom of oxygen (which turned out to be a mixture of 16O, 17O and 18O in a 3150:1:5 ratio with mean atomic mass number of 16,0035).


Dalton is also a placename in the United Kingdom:

  • Dalton, Dumfries and Galloway , Scotland
  • Dalton, Lancashire , England
  • Dalton, Hexham, Northumberland , England
  • Dalton, Ponteland, Northumberland , England
  • Dalton, Sowerby, North Yorkshire , England
  • Dalton, Richmond, North Yorkshire , England
  • Dalton, South Yorkshire , England

Also: Dalton in Furness , Cumbria, England

Dalton is also a placename in the United States of America:


Notable people whose surname is or was Dalton (with entries in Wikipedia):

Other uses

Last updated: 02-10-2005 05:52:01
Last updated: 02-25-2005 00:52:02