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Electronic Configuration - HSN forum

# Electronic Configuration

13 replies to this topic

### #1The Wedge Effect

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Posted 01 November 2005 - 09:21 PM

Hey, I know I'm not at school doing chemistry at AH, but I figured you might know a bit about electron configuration. So here's the problem. I'm not sure what to do for ions.

Here's the question:

3. Give the electronic configuration of:

a) Ca2+

c) O2-

p.s. it's stuff like 1S22s2 and whatever....

### #2KhalidBoussouara

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Posted 01 November 2005 - 10:02 PM

Ca is 1s22s22p63s23p64s2
but we lose 2 electrons in changing to a 2+ ion so the 4s2 becomes empty changing it to

Ca 2+ is then 1s22s22p63s23p6

O is 1s22s22p4
but we gain 2 electrons so that 2p shell gets an extra 2 in it to become

O2- is then 1s22s22p6
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### #3dfx

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Posted 01 November 2005 - 10:08 PM

Well Mg2+ would have lost 2 electrons from the outermost shell, so I take it would be:

1s 2s 2p

Rem the for shell n = 1 you have orbital s with a maximum of 2 electrons.

n = 2, shell 2s with max 2 electrons and 2p with max 6 electrons (technically 2px, 2py, and 2pz each with 2 so total equals 6.)

n = 3 repeats n = 2 with the additional 3d orbital.

Just remember 4s is preferentially occupied before 3d (roughly same energy levels.)

I know thats pretty vague but I hope it helps. Any good textbook should sort it out..

### #4Katrina

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Posted 01 November 2005 - 10:08 PM

oh see while we are on this topic can you help me with this question:

What is the maximum number of electrons that can be accommodated in a d subshell?

### #5dfx

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Posted 01 November 2005 - 10:11 PM

D subshell max is 10 electrons, cause shell n = 3 has max of 18 electrons in all configured in

### #6Katrina

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Posted 01 November 2005 - 10:13 PM

so n=1 has max of 2 n=2 has max of....8? and n=3 has max of 18. so wot about n=4?? how many n values can you get?

### #7The Wedge Effect

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Posted 01 November 2005 - 10:25 PM

Keep going...this is helping me with my uni work.

### #8Katrina

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Posted 01 November 2005 - 10:26 PM

how can you be doing the same stuff as me but you're not in my classes?

### #9Katrina

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Posted 01 November 2005 - 10:41 PM

wedge have you done anything on angular functions yet?

### #10dfx

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Posted 02 November 2005 - 12:32 AM

I'm not too sure about n = 4... I THINK it's 32.. but I dno if you'd really have to know how to write configurations for elements that far down.

### #11The Wedge Effect

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Posted 02 November 2005 - 01:10 PM

QUOTE(Katrina @ Nov 1 2005, 10:41 PM)
wedge have you done anything on angular functions yet?

Angular function...hmm...lemme think, is that to do with quantum numbers? You know...like n, l, m and s. I did that a few weeks ago and they were explaining how those functions were used in Schroedinger's equation and stuff like that.

### #12Katrina

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Posted 02 November 2005 - 06:10 PM

yes and you draw little circles on graphs, anyway do you know what the angular functions tell you about electron density?

### #13The Wedge Effect

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Posted 02 November 2005 - 07:05 PM

QUOTE(Katrina @ Nov 2 2005, 06:10 PM)
yes and you draw little circles on graphs, anyway do you know what the angular functions tell you about electron density?

I'm not sure, they haven't told us anything about electron density.

### #14Katrina

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Posted 08 November 2005 - 06:56 PM

20. Which of the following statements is INCORRECT?
(a) the orbital hybridisation of C in CH4 is sp2
(b) the orbital hybridisation of C in C6H6 is sp2
© the orbital hybridisation of C in C2H6 is sp3
(d) the orbital hybridisation of C in C2H4 is sp2
(e) the orbital hybridisation of C in C2H2 is sp

21. sp hybrid orbitals are formed in
(a) BeF2
(b) BCl3