Question

Which is a factor in determining the average atomic mass of an element?

Answer 1

The factor in determining the average atomic mass of an element is: 
B or 2 relative abundance of each isotope because the by looking at how many protons , electrons and neutrons the most isotope is of the element has relative abundance. 

Answer 2

Answer: The correct option is 2.

Explanation: Average atomic mass of an element is the summation of the relative abundance of each isotope multiplied by its atomic mass.

Mathematically,

$\text{Average Atomic Mass}=\sum_{i=1}^n(\text{Relative Abundance})_i\times (\text{Mass number})_i$

From the above relation, it is visible that the average atomic number of an element is dependent on relative abundance of each isotope.