Pulling electrons

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n2o* said:
What is the correct configuration for Zn2+?

Why is the answer [Ar]4s0 3d10 and not [Ar]4s2 3d8
Only the outermost electrons are extracted. So 4s.
 
Richnator said:
Only the outermost electrons are extracted. So 4s.

doesn't 4s fill before 3d? so wouldn't 3d be the outermost? Or are you just looking at n=4 vs. n=3?
 
n2o* said:
doesn't 4s fill before 3d? so wouldn't 3d be the outermost? Or are you just looking at n=4 vs. n=3?
You look at the primary quantum number for outermost, so 4 .
 
n2o* said:
doesn't 4s fill before 3d? so wouldn't 3d be the outermost? Or are you just looking at n=4 vs. n=3?

The 4s shell does normally fill up first, but for some transitional metals 1/2 or completely filled D subshells for are more stable. So in the case of Zn2+ it donates the 2 e- from the 4s to 3d to completely fill it making it most stable.
 
714guy said:
The 4s shell does normally fill up first, but for some transitional metals 1/2 or completely filled D subshells for are more stable. So in the case of Zn2+ it donates the 2 e- from the 4s to 3d to completely fill it making it most stable.

are u saying that if we were not dealing with a transition metal, the answer would be different?
 
n2o* said:
are u saying that if we were not dealing with a transition metal, the answer would be different?

yes b/c only transitionals metals occupy the 'd' subshell.
 
n2o* said:
What is the correct configuration for Zn2+?

Why is the answer [Ar]4s0 3d10 and not [Ar]4s2 3d8

You always take from s shell first then d (b/c 4s has a higher energy than 3d....and things like to have lowest energy to be more stable) Also, having a half filled or full electron shell is the more stable and preferred) For example, copper..Cu....the electron config is [Ar]4s1 3d10 not [Ar]4s2 3d9
 
Sweeti8286 said:
You always take from s shell first then d (b/c 4s has a higher energy than 3d....and things like to have lowest energy to be more stable) Also, having a half filled or full electron shell is the more stable and preferred) For example, copper..Cu....the electron config is [Ar]4s1 3d10 not [Ar]4s2 3d9

3d is a higher energy than 4s. n+l for 3d is 3+2, while 4s is 4+0. I do kind of understand the explanations that were given, tho.
 
n2o* said:
3d is a higher energy than 4s. n+l for 3d is 3+2, while 4s is 4+0. I do kind of understand the explanations that were given, tho.

3d is higher energy than 4s, you are correct - but that is only before any electrons are filled into either orbital. Once you fill the 4s orbital it becomes higher energy than 3d. I know its weird just try to think about it like this:

At first the 4s (when it is empty) is lower energy so it is filled before the 3d. Once electrons are occupying the 4s and 3d subshells, the 3d becomes more stable for whatever reason and now the 4s is higher energy. To get the most stable ion, you will remove from the 4s where possible.

There are exceptions but another rule as mentioned above is to always try to keep the d subshell half filled (5 electrons) or completely filled (10 electrons) whenever possible.
 
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