Usage of isotopes

Nonradioactive isotopes

• de-tuning of sonic speeds in sliding interfaces to reduce drag. See Friction.
• ...

Stable isotopes (ratio in earth's crust):

• ¹H 99.9885(70)% -- ²H (D) 0.0115(70)%
• ³He 0.000137% -- ⁴He 99.999863%

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• ⁶Li 7.4%
• ⁷Li 92.6%

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• ¹⁰B 19.9% -- ¹¹B 80.1%
• ¹²C 98.9% -- ¹³C 1.1%
• ¹⁴N 99.634% -- ¹⁵N 0.366%
• ¹⁶O 99.762% -- ¹⁷O 0.038% -- ¹⁸O 0.2%
• ¹⁹F 100%

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• ²⁰Ne 90.48% -- ²¹Ne 0.27% -- ²²Ne 9.25%

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• ²³Na 100%
• ²⁴Mg 78.99% -- ²⁵Mg 10.00% -- ²⁶Mg 11.01%

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• ²⁷Al 100%
• ²⁸Si 92.23% -- ²⁹Si 4.67% -- ³⁰Si 3.1%
• ³¹P 100%
• ³²S 95.02% -- ³³S 0.75% -- ³⁴S 4.21% -- ³⁶S 0.02%
• ³⁵Cl 75.77% -- ³⁷Cl 24.23%

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• ³⁶Ar 0.336% -- ³⁸Ar 0.063% -- ⁴⁰Ar 99.6%

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