Whlch element has the noble gas notation #[Kr]5s^2 4d^2#?

1 Answer
Dec 31, 2015

Answer:

The element is zirconium metal.

Explanation:

Krypton has atom number #36#. If 4 electrons are added, and the atom is neutral, #Z# (the atomic number) #=# #40# necessarily.

If #Z# #=# #40#, we have zirconium metal. How did I know this? Firstly, I assumed a neutral species. #36# + #4# #=# #40#. If #Z# #=# #40#, we know where to find it in the Periodic Table; I urge you to become familiar with it.

What if #Z# #=# #41#, or #Z# #=# #101#? What elements have I fingered?