## ranyai12 3 years ago What is the atom for the electron configuration [Ne]3s1 3p1? is it Mg or Ne-? and just to make sure,, this is an excited state right?

1. ranyai12

@eseidl

2. eseidl

Mg, excited state.

3. ranyai12

4. Rosie123

5. Rosie123

after this ?

6. eseidl

Yeah. Ok your electron "orbital" filling rules are 1s,2s,2p,3s,3p...

7. eseidl

s orbitals can take 2 electrons max. P orbitals can take 6.

8. ranyai12

but why isnt it Ne-?

9. eseidl

We fill 3s BEFORE 3p. Since 3s only has one electron in the s orbital, but also has one in the p orbital, it is an excited state.

10. ranyai12

oh it it because itll give it an extra electron?

11. ranyai12

is it*

12. eseidl

Now why is it Mg...well, Mg is atomic number 12. So, the neutral atom has 12 electrons. We get: \[1s^2,2s^2,2p^63s^2\]for the neutral atom. But if we exited the atom, bumping 1 electron into the 3p orbital, we have a (slightly) excited Mg atom.

13. ranyai12

oh ok thanks!!!

14. eseidl

Why isn't it Ne-...

15. eseidl

well, Ne- has 11 electrons. We get:\[1s^2,2s^2,2p^63s^1\]Not enough electrons to be Ne-

16. ranyai12

oh ok! thanks again!

17. eseidl

It could be an exited state of \[Ne^{-2}\] though....

18. eseidl

But yeah, I think that narrows it down for you :)