The average atomic mass of zirconium is A) less than 90 because the atomic mass only depends on the number of protons in the atom. B) 90 because ⁹⁰Zn has the highest natural abundance. C) greater than 90 but less than 96 because the atomic mass takes into account the abundance of all naturally occurring isotopes. D) 96 because the atomic mass is the mass of the highest naturally occurring isotope. E) greater than 96 because the atomic mass is the sum of masses of the naturally occurring isotopes.

Question

Quizplus · Accepted Answer

The atomic mass of an element takes into account the abundance of all naturally occurring isotopes, not just the most abundant one. While zirconium does have a relatively high abundance of the isotope ⁹⁰Zn, it also has other isotopes present. Therefore, the average atomic mass of zirconium is expected to be greater than 90 but less than 96.

The Average Atomic Mass of Zirconium Is