Question

The element chromium has four naturally occurring isotopes. What is the average atomic mass of chromium, using `""^50Cr=4.34%, ""^52Cr=83.79%, ""^53Cr=9.50%, ""^54Cr=2.37%`?

Answer 1

The average atomic mass is simply the weighted average of the individual isotopic masses.

Explanation:

So let us take the weighted average of your isotopes:

`(50xx0.0434 + 52xx0.8379+53xx0.095+54xx0.0237)g*mol^-1` `=` `??`

The final answer should be close to `52` `g*mol^-1` because `""^52Cr` is the most abundant isotope.