Question 2

The three stable isotopes of neon: ^{20}Ne_{10}, ^{21}Ne_{10} and ^{22}Ne_{10} 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.

Answer

Atomic mass of ^{20}Ne_{10}, m_{1} = 19.99 u

Abundance of ^{20}Ne_{10}, η_{1} = 90.51%

Atomic mass of ^{21}Ne_{10}, m_{2} = 20.99 u

Abundance of ^{21}Ne_{10}, η_{2} = 0.27%

Atomic mass of ^{22}Ne_{10}, m_{3} = 21.99 u

Abundance of ^{22}Ne_{10}, η_{3} = 9.22%

The average atomic mass of neon is given as:

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