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→Experimental verification: move isotope numbers to standard top-left position
They bombarded [[Lithium]] atoms with [[protons]] having a [[kinetic energy]] less than 1 [[Electron-Volts|MeV]]. The result were two (slightly less heavy) [[α-particle]]s, for which the [[kinetic energy]] was measured as 17.3 MeV
They bombarded [[Lithium]] atoms with [[protons]] having a [[kinetic energy]] less than 1 [[Electron-Volts|MeV]]. The result were two (slightly less heavy) [[α-particle]]s, for which the [[kinetic energy]] was measured as 17.3 MeV
:::::<math>{}_3\mathrm{Li}^7\, +\, {}_1\mathrm{H}^1\,\rightarrow\,2\, {}_2\mathrm{He}^4</math>
:::::<math>{}_3^7\mathrm{Li}\, +\, {}_1^1\mathrm{H}\,\rightarrow\,2\, {}_2^4\mathrm{He}</math>
The mass of the particles on the left hand side is 8.0263 [[atomic mass units|amu]]s, the mass on the right hand side ''only'' 8.0077 amu.<ref>Gerard Piel ''The age of science: what scientists learned in the 20th century'', Basic Books, 2001, p. 144-145</ref> The difference between this masses is .00186 amu, which results in the following back-of-an-envelope calculation:
The mass of the particles on the left hand side is 8.0263 [[atomic mass units|amu]]s, the mass on the right hand side ''only'' 8.0077 amu.<ref>Gerard Piel ''The age of science: what scientists learned in the 20th century'', Basic Books, 2001, p. 144-145</ref> The difference between this masses is .00186 amu, which results in the following back-of-an-envelope calculation: