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Boron occurs in nature in the form of tw...

Boron occurs in nature in the form of two isotopes `underset(5)overset(11)B` and `underset(5)overset(10)B` in ratio of `81%` and 19% respectively. Calculate its average atomic mass.

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Average atomic weight `=("mass number x percentage")/("total percentage") =(11 xx 81 + 10 xx 19)/100 = 10.81`
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