More chemistry help God I hate chemistry

[1MileCrash]

Homework Statement

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Homework Equations

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The Attempt at a Solution

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Anyone want to explain, slowly, apparently because I'm an idiot, just what's wrong here?

http://img204.imageshack.us/i/25637178.png/

http://img543.imageshack.us/i/74013245.png/

 

[QuarkCharmer]

Looks like they want you to give the electron config of various Atoms/Ions/Molecules.

Transition metals (well, their ions) are pretty annoying sometimes, I found a great explanation here:
http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch12/trans.php#electron

(Those images are no longer working?)

 

[1MileCrash]

I don't understand, for the Molybdenum ion I gave the exact electron config of Yttrium, is that not correct?

 

[QuarkCharmer]

Mo is an exception:

http://www.mpcfaculty.net/mark_bishop/anomalies.htm

 

[cep]

There is a strong preference for half-filled or full d-orbitals (5 or 10 electrons). Any time you have a nearly half-filled or full d-orbital and some s electrons to spare, you're probably looking at an exception.