biostudent101

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Dec 24, 2008
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Q314. how many lone electron pairs are found in AsBr3? the solution manual says 10 lone electron pairs. I don't understand where he got 10 from?

Thanks
 
May 28, 2009
130
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Status
Pre-Dental
Q314. how many lone electron pairs are found in AsBr3? the solution manual says 10 lone electron pairs. I don't understand where he got 10 from?

Thanks

Try to draw it out:

As has 5 total e-, sharing three , Br has 7 valence, sharing one.
Put 3 Br's around the central As and add up the pairs= 10 e- pairs.
 
May 15, 2009
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Dental Student
As = Group 5

Br = Group 7

5 + 3(7) = 26

Three bonds connect Br to the central As atom, so:

26 - 3(2) = 20 --># of lone pairs

Now distribute these 20 electrons around the Br and then As atoms:


How many pairs of red dots do you see?
10