What is average atomic mass and how is it calculated? The average atomic mass for an element is calculated by summing the masses of the element’s isotopes, each multiplied by its natural abundance on Earth. When doing any mass calculations involving elements or compounds, always use average atomic mass, which can be found on the periodic table.What is the formula for average atomic mass?
Atomic mass = Number of protons + number of neutrons + number of electrons. In other words, when proton, electrons, and neutrons of one atom are added together then this is named as average mass of the atom. As compared to neutrons and the protons, electrons are so limited in count that it has only a small affect on the calculation.How is the average of atomic mass determined?
Average atomic mass = f 1 M 1 + f 2 M 2 + … + f n M n where f is the fraction representing the natural abundance of the isotope and M is the mass number (weight) of the isotope. The average atomic mass of an element can be found on the periodic table, typically under the elemental symbol.