valence electron.

[joonkimdds]

I always ask a basic question so I am kinda embarassed but I just want to know so plz don't mind

I just started to read Kaplan blue book and it's page 201. I understand that iron has 8 valence electron becuz 2 in its 4s subshell and 6 in 3d subshell

I don't understand why selenium has 6 valence electrons. why don't we count electrons in 3d subshell? Does this mean we never count the electrons in D subshells?

and why does Sulfur in a sulfate ion has 12 valence electrons?
the explanation says 6 from sulfur and 6 from oxygen when they are bonded. but the question is asking surfur valance electron not the sulfate ion valanece electron. it also says 8 goes to 3s and 3p subshell but the other 4 electrons go to 3d subshell. So once again, do we ignore D subshells and thus octet rule(8 electrons are max) always apply?

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[DAT Destroyer]

I always ask a basic question so I am kinda embarassed but I just want to know so plz don't mind

I just started to read Kaplan blue book and it's page 201. I understand that iron has 8 valence electron becuz 2 in its 4s subshell and 6 in 3d subshell

I don't understand why selenium has 6 valence electrons. why don't we count electrons in 3d subshell? Does this mean we never count the electrons in D subshells?

and why does Sulfur in a sulfate ion has 12 valence electrons?
the explanation says 6 from sulfur and 6 from oxygen when they are bonded. but the question is asking surfur valance electron not the sulfate ion valanece electron. it also says 8 goes to 3s and 3p subshell but the other 4 electrons go to 3d subshell. So once again, do we ignore D subshells and thus octet rule(8 electrons are max) always apply?

Selenium is in the Oxygen family, so you should immediately realize six valence electrons. However, if you wrote the configuration, we would see [Ar] 4s23d104p4 the valence shell is 4 thus we have 2 + 4 or 6 valence electrons here. The second question has little meaning,,,,S will have 6 valence electrons, but I think you copied the question wrong or the problem was not stated correctly. Regards, Dr. Jim Romano NYU Orgoman.com

 

[RozhonDDS]

I always ask a basic question so I am kinda embarassed but I just want to know so plz don't mind

I just started to read Kaplan blue book and it's page 201. I understand that iron has 8 valence electron becuz 2 in its 4s subshell and 6 in 3d subshell

I don't understand why selenium has 6 valence electrons. why don't we count electrons in 3d subshell? Does this mean we never count the electrons in D subshells?

and why does Sulfur in a sulfate ion has 12 valence electrons?
the explanation says 6 from sulfur and 6 from oxygen when they are bonded. but the question is asking surfur valance electron not the sulfate ion valanece electron. it also says 8 goes to 3s and 3p subshell but the other 4 electrons go to 3d subshell. So once again, do we ignore D subshells and thus octet rule(8 electrons are max) always apply?

sulfur is one of those elements that can expand its octet, that why the sulfate ion has 12 valence electrons.

 

[DAT Destroyer]

True.... sulfur has D orbital vacancy thus can expand its octet. Elements such as Os, P, and many transition elements can also expand their octets due to this D orbital vacancy.

 

[RozhonDDS]

True.... sulfur has D orbital vacancy thus can expand its octet. Elements such as Os, P, and many transition elements can also expand their octets due to this D orbital vacancy.

i believe the rule is any element on the 3rd period or below it can expand their octet!