Answer:
The atomic mass is the mass of an atom. Although the SI unit of mass is the kilogram, atomic mass is often expressed in the non-SI unit atomic mass unit or unified mass or dalton.
To calculate the atomic mass the step we should follow is as follows:-
Check the amount that is present in the earth crust
Multiply it with the type of it
Hence, the atomic mass of the phosphorus is:-
\frac{(29 * 35.5) \ + (30 * 42.6)\ + (31 * 21.9)}{100}
100
(29∗35.5) +(30∗42.6) +(31∗21.9)
After solving it,
\frac{029.5 + 1278 + 678.9}{100}
100
029.5+1278+678.9
= 29.864 amu.29.864amu.
Hence, the atomic mass of the Phosphorus is 29.864amu
