Question

Elemental chlorine consists mainly of two isotopes: `""^35Cl` of `75%` abundance; and `""^37Cl`... What is the average atomic mass of chlorine?

Answer 1

About `35.5*"amu"`

Explanation:

Atomic mass is the weighted average of the individual isotopes.

And thus average atomic mass is given by the expression:

`(0.75xx35(""^35Cl) +0.25xx37(""^37Cl))*"amu"=`

`35.5*"amu"`