Question

Does potassium metal have isotopes?

Answer 1

Potassium does indeed have isotopes. The weighted average of the individual isotopes is the average atomic mass.

Explanation:

This site reports that there are 24 isotopes of potassium. Of course, since it is potassium, `Z=19` (why?).

The common isotopes are `""^39K (93.3%)`, and `""^41K (6.7%)`. If we take the weighted average of these 2 major isotopes we get very close to the average atomic mass, `39.0983" amu"`.