[SerraAngelOKC]

Hi Everyone-

Can anyone help me to better understand how to find the capacity for orbitals?  Is there a formula?  Here is what I am looking at:

I have a teacher who has us do "pre-lecture" quizzes online, no problem except that I am stuck on this one sections on orbitals.  One of the questions is to find the electron capacity of the subshell 4s.  We are to find the electrons and how many orbitals.  My answer is 32 electrons in 4 orbitals.  Am I right?  

I would appreciate any *delete me*  I am trying to get an A in this class (Intro to Chemistry) so I can have a solid foundation for the other chemistry classes I am required to take for my forensic science degree.  Thanks again in advance!  Sorry for the long post.   :bye2: :Confuzzled:

[mike]

There are a few different types of orbitals for example, s, p, d and f.

There is only one type of s orbital, s orbitals can hold a total of two electrons.

There are 3 types of p orbitals (each able to hold two electrons) so p orbitals hold a maximum of 6 electrons.

There are 5 types of d orbitals (each able to hold two electrons) so d orbitals can hold a maximum of 10 electrons.

Look at the periodic table and you will see the s, p, d and f sections, sometimes this helps visualise how the orbitals are filled.

So a 4s subshell will hold a maximum of two electrons. If this shell did contain two electrons then this means all of the shells "below" this one are also full (as they must fill in order):

1s2 2s2 2p6 3s2 3p6 4s2

This is the electronic configuration of Ca.

4s contains the valence electrons.

Note that Ca has 20 electrons.

It can also be written as [Ar] 4s2

as everything up to Ar is filled, so it is "easy" for Ca to lose the last two electrons (the valence electrons) to become Ca2+ which makes its electronic configuration the same as the noble gas Ar, which is quite stable (ie lower energy)

I hope this helps, let me know if it is too complicated (or not complicated enough).

Mike

[jdurg]

Yes, that is a very good general rule, but as you get into higher and higher atomic numbers, the energy levels between the various subshells start to even out and you'll see 'odd' fillings as you move into the transition metals.  (Once the 3d shell starts to fill, all hell tends to break loose).  

[SerraAngelOKC]

Thanks for the *delete me*  I think I got it now.  =)