The three stable isotopes of neon `._10Ne^(20), ._10Ne^(21)` and `._10Ne^(22)` have respective abundances of `90.51%,0.27%` and `9.22%`. The atomic masses of the three isotopes are `19.99u, 20.99u` and `21.99u` respectively. Obtain the average atomic mass of neon.

Explanation

Given,
Atomic mass of `""_(10)Ne^(20) = 19.99 u`
Atomic mass of `""_(10)Ne^(21) = 20.99 u`
Atomic mass of `""_(10)Ne^(22) = 21.99`u
Relative abundance of `""_(10)Ne^(20) = 90.15%`
Relative abundance of `""_(10)Ne^(21) = 0.27%`
Relatvie abundance of `""_(10)Ne^(22) = 9.22%`
The average atomic mass of neon is
`m(Ne) = (90.51 xx 19.99 + 0.27 xx 20.99 + 9.22 xx 21.99) xx 10^(-2) = 20.17`u