Difference between revisions of "Isotope"
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Atoms can be simply described as consisting of [https://en.wikipedia.org/wiki/Proton protons], [https://en.wikipedia.org/wiki/Electron electrons], and [https://en.wikipedia.org/wiki/Neutron neutrons]. Isotopes of the same element differ by the number of neutrons in the nucleus, resulting in different mass. | Atoms can be simply described as consisting of [https://en.wikipedia.org/wiki/Proton protons], [https://en.wikipedia.org/wiki/Electron electrons], and [https://en.wikipedia.org/wiki/Neutron neutrons]. Isotopes of the same element differ by the number of neutrons in the nucleus, resulting in different mass. | ||
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| + | ==<div id="delta_notation">The δ-notation</div>== | ||
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| + | Because relative differences in isotope ratios are more precisely detected than the absolute isotopic ratios, they are commonly reported in the δ-notation: | ||
| + | <div style="text-align: center;"> <math> \delta=(\frac{R_{x}-R_{std}}{R_{std}})\times 1000 </math> </div> | ||
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| + | where <math> R </math> is the ratio of the abundance of the heavy to the light isotope, <math> x </math> is the measured sample, and <math> std </math> is the standard. For the element [[Stable oxygen isotopes | oxygen]], <math> R </math> is given by <sup>18</sup>O/<sup>16</sup>O. | ||
Revision as of 15:05, 15 January 2016
Atoms can be simply described as consisting of protons, electrons, and neutrons. Isotopes of the same element differ by the number of neutrons in the nucleus, resulting in different mass.
The δ-notation
Because relative differences in isotope ratios are more precisely detected than the absolute isotopic ratios, they are commonly reported in the δ-notation:
where 
is the ratio of the abundance of the heavy to the light isotope, 
is the measured sample, and 
is the standard. For the element oxygen, is given by 18O/16O.
