MCAT Question A Day - 10/23/14 - Answer!
Which of the following species has an unpaired electron in its ground-state electronic configuration?
A. Ne
B. Ca+
C. Na+
D. O2-
B is correct. The quickest way to see this is by realizing that atoms like to form ions with electron configurations similar to the nearest noble gas. Of course a noble gas does not have any unpaired electrons. You should recognize that Ca likes to form a 2+ ion not a 1+ ion.
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B is correct. The quickest way to see this is by realizing that atoms like to form ions with electron configurations similar to the nearest noble gas. Of course a noble gas does not have any unpaired electrons. You should recognize that Ca likes to form a 2+ ion not a 1+ ion.
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