Weighted Average Atomic Mass of Iron

Weighed average atomic mass of iron

A weighted average average atomic mass for a specific element refers to the average mass all of its atoms, as opposed to 1/12th that of a single carbon-12. This average is determined by taking into account the mass of each of the element’s isotopes and the abundance of each isotope in nature. There are three isotopes of iron that naturally occur: Fe-54 (56), and Fe-57%. Fe-54 is abundant at 6%; Fe-56, 92% and Fe-57, respectively (Khan Academy 2020). We need to add the masses of all the isotopes together in order to calculate the average weighted atomic iron mass. Fe-54 has a mass of 53.939 amu. Fe-556 has a mass of 55.935 amu and Fe-57 has 58.935 amu. Khan Academy 2020. Each mass can be multiplied by its amount to obtain the following:
Fe-54: 53.939 * 0.06 = 3.236 amu
Fe-56: 55.