m a = 4.0026 ⋅ 99.9999% + 3.0160 ⋅ 0.0001% = = 4.0025959974 + 0.000003016 = = 4 , 0025990134 [ am u ]
The average atomic mass of helium is 4,0025990134 amu.
The average atomic mass of helium, calculated using its isotopes' masses and their abundances, is approximately 4.0026 amu. This value reflects the prevalence of helium-4 compared to helium-3. The calculation method involves multiplying each isotope's mass by its relative abundance and summing the results.
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