Question

Which best describes the definition for the atomic mass of an element?

Answer 1

Answer:

It is a weighted average of the masses of an element’s isotopes.

Explanation:

The best definition of the atom mass of an element is that it is a weighted average of the masses of an element's isotopes.

• Isotopes of an element have the same electronic configuration but differ in only their masses.
• The atomic mass of an element can be derived from the geonormal abundances of this isotopes.
• It is the average of all the isotopes of an element.

 Atomic mass  = ∑m$_{i}$ a$_{i}$

where m$_{i}$ is the mass of the isotope i

            a$_{i}$ is the abundance of the isotope i