atomic theory

jinzen · Junior Member Joined: 02 Apr 2005 Posts: 4

This was an assignment given to us about atomic theory. The questions are in quotes and my answers/query are below the quotes.

RobJim · Posted: Sun Apr 03, 2005 2:21 am Post subject:

Our spin QNs are +1/2 and -1/2, yes. Our magnetic quantum numbers are the integers from -l to l. There are two kinds of m; ml, which is the magnetic QN, and ms which is the spin QN.

The magnetic QNs are different because ours go from -l to l, giving us 2l+1 MQNs (or orbitals with the same l values), and theirs go from 0 to l, giving them l+1 MQNs (or orbitals with the same l values).

This i'm not so sure of, since i don't understand their spin quantum numbers. By +1/2, 0, -1/2... does tha "0" mean there can be a orbital that can be empty?

I think the point is that instead of two electrons fitting in a single orbital by the Pauli exclusion principle, three can.

Here's element 24 in this other universe:

1s3 2s3 2p6 3s3 3p6 4s3

The atomic numbers of the first three noble gases would be 3, 12, 21.

The idea you're supposed to be learning is that the number of possible spin quantum numbers equals the maximum number of electrons in an orbital, and the number of possible magnetic quantum numbers equals the maximum number of orbitals of the same principal quantum number n and azimuthal quantum number l (or letter - s, p, d,...)

In our universe we can have two electrons per orbital and 2l+1 orbitals of the same n and l values, while the other universe would have three electrons and l+1 orbitals. So, one s, two p, three d for the other universe.

Does that clear things up?

Mitch · Regular Joined: 25 Mar 2005 Posts: 29 Location: Berkeley

I'm glad you answered him, he's been posting that question all over the internet.

Hmmmm..... The forum seems to be double posting messages.

jinzen · Junior Member Joined: 02 Apr 2005 Posts: 4

RobJim · Posted: Sun Apr 03, 2005 10:50 pm Post subject:

jinzen · Junior Member Joined: 02 Apr 2005 Posts: 4

did you not see my reply, RobJim o_o I still had some questions

RobJim · Posted: Thu Apr 07, 2005 7:39 am Post subject:

No, your periodic table is not correct. Your s-block should have 3 elements per period, for one thing. Do you understand what I mean by that?

So, say for 3l = f has 7 orbitals... in their universe it would be 4 orbitals in theirs? because of l+1. You just basically add one to the before orbital.

Correct.

Would the number of having a full orbital (eight) be the same as ours?

Nope. First of all, in our universe a full orbital has two electrons. I think you mean a full energy level in our universe has eight electrons, as long as it's not the first one (which holds two) and d and f orbitals aren't taken into consideration for the higher ones.

The reason there are eight electrons is that there are four orbitals in the energy level - one s and three p - and each holds two electrons. In this alternate universe, there are different numbers of s and p orbitals, and each orbital holds a different number of electrons. That should be enough information for you to figure out how to put together the alternate universe periodic table.

jinzen · Junior Member Joined: 02 Apr 2005 Posts: 4

Ohhh i see Surprised

I'll fix that right up.

Thanks again!! Very Happy