## Valence Electrons in D Subshell

Wendy 1E
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### Valence Electrons in D Subshell

How do you determine the number of valence electrons in the d subshell? On A.1 part c, they asked for the number of valence electrons in Manganese and the answer was 7. How did they get to this answer?

MAC 4G
Posts: 121
Joined: Wed Sep 18, 2019 12:16 am

### Re: Valence Electrons in D Subshell

If you find its electron configuration, you'll find that it's [Ar]4s^2 3d^5. You can see here that there are 2 in the s and 5 in the d, so 2+5 = 7 valence e-

MAC 4G
Posts: 121
Joined: Wed Sep 18, 2019 12:16 am

### Re: Valence Electrons in D Subshell

Sorry it should be [Ar]3d^5 4s^2

Posts: 87
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### Re: Valence Electrons in D Subshell

The number of valence electrons is all of the electrons that are not a part of the inner core. Therefore any electron past the abbreviation we used with [X] where X is a noble gas, will be a valence electron regardless of its subshell or energy level for our purposes in calculating the amount of valence electrons. Therefore in Manganese, where the configuration would be [Ar] 3d5 4s2 we can count seven past the argon. Hope this helps!

chemboi
Posts: 101
Joined: Sat Jul 20, 2019 12:16 am

### Re: Valence Electrons in D Subshell

Valence electrons includes all e- not part of the "noble gas core", so you count the 5 ei in the d state in addition to the 2 e- in the s state.

chemboi
Posts: 101
Joined: Sat Jul 20, 2019 12:16 am

### Re: Valence Electrons in D Subshell

As this (https://www.quora.com/Why-does-titanium ... in-group-3) answer to a similar question explains, even though the 3d electrons are not in the n=4 level, their energy is so close to that of the 4s electrons that all are considered valence electrons that can participate in bonding.