The three stable isotopes of neon: 20Ne10, 21Ne10 and 22Ne10 have respective abundances of 90.51%, 0.27% and 9.22%. The atomic masses of the three isotopes are 19.99 u, 20.99 u and 21.99 u, respectively. Obtain the average atomic mass of neon.
Atomic mass of 20Ne10, m1 = 19.99 u
Abundance of 20Ne10, η1 = 90.51%
Atomic mass of 21Ne10, m2 = 20.99 u
Abundance of 21Ne10, η2 = 0.27%
Atomic mass of 22Ne10, m3 = 21.99 u
Abundance of 22Ne10, η3 = 9.22%
The average atomic mass of neon is given as:
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(a)
(b)
(c)
(d)
(e)
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