Question

How do you find the atomic mass number of phosphate?

Answer 1

Atomic mass number:

1. The mass number of an atom, also known as the atomic mass number or nucleon number, is the total sum of protons and neutrons present in its nucleus.
2. For phosphate, the chemical formula ${{\mathrm{PO}}_4}^{-3}$ has one phosphorous atom and four oxygen atoms.
3. The total mass of phosphate $=$Mass of $1$phosphorous atom $+$Mass of $4$oxygen atom.
4. Mass of phosphorous $=30.97$amu and mass of four oxygen atom$=4\times 15.99\Rightarrow 63.96$
5. Total mass of phosphate $=30.97+63.96\Rightarrow 94.93$amu.