What element is represented #[Kr]5s^1#?

1 Answer
Dec 4, 2016

Well if it's a neutral element, the element is #"rubidium."#

Explanation:

Look at a copy of the the Periodic Table, and look at the 4th and 5th Periods. Krypton is an inert gas that ends a Period; rubidium is an alkali metal that begins the next Period, the 5th Period.

In practice, we don't even have to know about electronic configuration. #Kr# has #Z=36#; add an electron, and a nuclear proton (and possibly a few more neutrons), we get #Z=37#, the #"atomic number"# of #"rubidium"#. #"Claro?"#