# #of valence electrons

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#### datdat

##### Full Member
if the e-config is

1s2 2s2 sp6 3s2 3p6 4s2 3d10 4p6 4d5 5s2

what is the valence shell and electron numbers in it?

#### dentrilla

##### Full Member
10+ Year Member
valence electrons are in the last shell (valence shell?), which would be shell #5. aka 5s2 are ur valence electrons, if there had been 3 more e-'s then the valence e-'s would be 5s2,5p3..

#### dentrilla

##### Full Member
10+ Year Member
Oops, in my example above, if there had been 3 more then there would be no need to hop up to the 5s orbital. it woulda been 4s2 4p6 4d10 as ur valence e-'s.

#### ttran9229

##### Full Member
I see 7 valence electrons.

#### suhshi

##### Full Member
10+ Year Member
Oops, in my example above, if there had been 3 more then there would be no need to hop up to the 5s orbital. it woulda been 4s2 4p6 4d10 as ur valence e-'s.

wait do you mean 4d8?

#### nze82

##### Full Member
5s and 4d represent your valence "shell" and the sum of the electrons in 5s and 4d represent the number of your valence electrons (7)!

#### dentrilla

##### Full Member
10+ Year Member
wait do you mean 4d8?
nope, in his initial question if you added 3e- those e- in the 5s2 orbital would join up with the 4d5 plus the three we added making the highest energy orbital 4d10.

#### dentrilla

##### Full Member
10+ Year Member
Hmm, about those valence e- in his initial question I didnt know that when e- from the 4d orbital jump up to 5s in order to be more stable (having the 4d orbital exactly half full) the half filled 4d orbital is considered valence.. thanks for the correcting

#### nze82

##### Full Member
nope, in his initial question if you added 3e- those e- in the 5s2 orbital would join up with the 4d5 plus the three we added making the highest energy orbital 4d10.
What on earth are you talking about?! Electrons just don't move around for no reason.
This is really not that complicated.
In this particular question, the # of valence electrons is 7.

#### dentrilla

##### Full Member
10+ Year Member
What on earth are you talking about?! Electrons just don't move around for no reason.
This is really not that complicated.
In this particular question, the # of valence electrons is 7.

I know that(now), I was talking about if we were to add 3e- to the total number of e-. I was just showing an example and asking if it was correct.

#### nze82

##### Full Member
I know that(now), I was talking about if we were to add 3e- to the total number of e-. I was just showing an example and asking if it was correct.
Oh OK!!
I was complete confused by that. I thought you're referring to this particular question.
Sorry...