Question

Question #8d3ca

Answer 1

`"[Ar]3d"^10"4s"^2"4s"^6` would be the most common answer so that the valence electrons will be written together. However, some instructors will prefer the sublevels to be written in order of increasing energy, which would be `"[Ar]4s"^2"3d"^10"4p"^6"`. Ask your instructor what he or she prefers.

Explanation:

The Aufbau diagram shows the order in which the sublevels fill according to their energies. You can see that the `"3d"` sublevel fills after the `"4s"` sublevel and before the `"4p"` sublevel.

Answer 2

It is:
<Ar> 3d10 4s2 4p6

Explanation:

Firstly, electronic distribution of elements is carried out using the closest possible noble gas in electronic configuration. (i.e. Krypton has an atomic number of 36, so the closest noble gas in configuration is Argon which has 18 electron not neon which has 10 electron!).

Secondly, we use the order of ((3d then 4s then 4p)) Not ((4s then 3d then 4p)). This is according to the principle of building up (Auf Bau Principle) in electronic distribution or configuration. (i.e. Electrons must fill the lower energy level then the higher)------ 3d<4s<4p in energy...