Radicals in hybridization and VSEPR problems

[minionphil]

Hi guys,

I am confused by whether or not a radical counts as an electron cloud.

In the 2017 version of DAT Destroyer General Chem section #329, it asks us to consider NO2 and estimate the ONO bond angle. The answer is "over 120" (vs. "under 120" and "120"), implying that the radical counts as an electron cloud. (Just does not take as much space as a lone pair. )

However, in Bootcamp Organic Chem test #2, last question, there is a 1,4-dimethylbenzene. On one of the methyl groups, instead of having 3 bonds to hydrogen, the carbon has 2 bonds to hydrogen and a radical (and of course a bond to the benzyl). The answer says that the carbon with the radical is sp2 hybridized, instead of sp3, implying that radical does not count as an electron cloud when determining hybridization.

I guess my question is, is there a "double standard" for radicals when it comes to determining the molecular structure vs. determining the hybridization? Or did DAT Destroyer or Bootcamp made a mistake?

Any clarification is greatly appreciated. Thanks in advance!

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[Queen Beach]

Both are right.
What's confusing you is what you think the destroyer ? is implying.
The radical (the e^- that is acting like a pair of e^-) does not have the strength to bend the O atom very far to 120 degrees as if it had a pair of e^-, but it's still considered bent. Therefore, over 120 degrees is correct because it's straighter (geometry 101: a straight line=180 degrees)

 

[minionphil]

Both are right.
What's confusing you is what you think the destroyer ? is implying.
The radical (the e^- that is acting like a pair of e^-) does not have the strength to bend the O atom very far to 120 degrees as if it had a pair of e^-, but it's still considered bent. Therefore, over 120 degrees is correct because it's straighter (geometry 101: a straight line=180 degrees)

Got it. Thanks!