Question

B has two isotopes B10 19% and B11 81% the atomic mass of B is

Answer 1

$atomic \: mass = \frac{10 \times 19 + 11 \times 81}{100} \\ = \frac{190 + 891}{100} \\ = \frac{1081}{100 } \\ = 10.81$

Atomic mass is 10.81

Answer 2

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$atomic \: mass = \frac{10 \times 19 + 11 \times 81}{100} \\ = \frac{190 + 891}{100} \\ = \frac{1081}{100 } \\ = 10.81$

Atomic mass is 10.81

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