How many electrons are there in a neutral atom of Kr-85?

1 Answer
Dec 29, 2016

Got a Periodic Table?


For #"krypton"#, #Z=36#. By definition, this means that there are 36 positively charged particles in the krypton nucleus. Since it is the #""^85Kr# isotope, this also means that there are #85-36=49# neutrons in this nuclide but this is not germane to the problem.

So if there are 36 positively charged particles, 36 protons, how many electrons, fundamental particles of NEGATIVE charge, whizzing about the nucleus if the atom is neutral? The answer should be clear.