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Whole Number Rule

The Whole Number Rule states that the masses of the elements are whole number multiples of the mass of the hydrogen atom.^[1] The rule can be formulated from Prout's hypothesis put forth in 1815.^[2] In 1920, Francis W. Aston demonstrated through the use of a mass spectrometer that apparent deviations from the rule were due to the existence of isotopes.^[3]

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References

^ Budzikiewicz H, Grigsby RD (2006). "Mass spectrometry and isotopes: a century of research and discussion". Mass spectrometry reviews 25 (1): 146-57. doi:10.1002/mas.20061. PMID 16134128.
^ Prout, William (1815). "On the relation between the specific gravities of bodies in their gaseous state and the weights of their atoms.". Annals of Philosophy 6: 321–330. Retrieved on 2007-09-08.
^ Aston, Francis W. (1920). "The constitution of atmospheric neon". Philosophical Magazine 39 (6): 449-455. Retrieved on 2007-09-08.

Harkins WD (1925). "The Separation of Chlorine into Isotopes (Isotopic Elements) and the Whole Number Rule for Atomic Weights". Proc. Natl. Acad. Sci. U.S.A. 11 (10): 624–8. PMID 16587053.

Categories: Mass spectrometry | Chemical elements