Physicist and chemist — Francis William Aston (Harborne, Birmingham 1877 – Cambridge 1945) was a British chemist and physicist, awarded the Nobel Prize in Chemistry in 1922. He worked at Cambridge in the Cavendish Laboratory under J.J. Thomson. He is famous for having invented the mass spectrograph, an instrument capable of separating atoms according to their mass-to-charge ratio. With it he discovered that many elements exist in forms with different masses, isotopes, and measured their masses with great precision, formulating the ‘whole number rule’. His measurements also revealed the ‘mass defect’ of nuclei, opening the way to understanding nuclear binding energy.
Curiosity
His precise measurements of the mass defect in nuclei anticipated the idea that enormous quantities of energy could be released from matter, and as early as 1922 he publicly hinted at this possibility.
Theories and contributions
- Mass spectrograph — Instrument that separates ions according to their mass-to-charge ratio, making it possible to identify and weigh isotopes.
- Whole number rule — The atomic masses of isotopes are close to whole numbers relative to the reference atom (aside from the mass defect).
Present in chapters
Linked atoms
1 linked atom.