Question

The need of the term average atomic
mass.​

Answer 1

Answer:

This is the term used in periodicity in periodic Table by Dobernier.

Answer 2

$\huge \mathfrak \green {hello}$

The average atomic mass of an element is the sum of the masses of its isotopes, each multiplied by its natural abundance (the decimal associated with percent of atoms of that element that are of a given isotope). The atomic number of chlorine is 17 (it has 17 protons in its nucleus).

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