Question

calculate the percentage of higher isotope of neon

Answer 1

let x be the percentage of ne atoms that are Ne-22.Then 100-x is the percentage that are Ne-20.The overall atomic mass is the weighted average,so
20.2=(22x+20(100-x))/100
solve for x

Answer 2

Explanation:

the total mass is taken to be average of the two isotope.

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