Question

Of all boron atoms, 19.9%% are boron-10, which have a mass of 10.01294 amu. The other 80.1% of boron atoms are boron-11 and these have a mass of 11.00931. Calculate the average atomic mass of boron.

Answer 1

Answer:

10.81 amu

Explanation:

The average atomic mass of Boron can be calculated as follows :

$A=19.9\%\ \text{of}\ 10.01294 +80.1\%\ \text{of}\ 11.00931\\\\A=\dfrac{19.9}{100}\times 10.01294 +\dfrac{80.1}{100}\times 11.00931\\\\A=10.81\ \text{amu}$

So, the average atomic mass of boron is 10.81 amu.