VSEPR formula question for CHM

[joonkimdds]

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Do u guys remember the questions that asks about shapes and angles in Lewis structures? According to my professor, there can be about 12 each.
They are linear, V shaped, bent, trigonal planar, trigonal pyramid, t shaped, tetrahedral, seesaw, trigonal bipyramid, octahedral, square planar, and square pyramid. Their angles are 180, <120, <109.5, 120, <109.5, <90, 109.5, >90, 90/120, 90, 90, >90.

There were questions about these 12 in my class test, and since there are too many, my professor allowed me to use the sheet that has these information.

I just looked at the Kaplan Blue Book, and it only shows 5 different kinds; linear, trigonal planar, tetrahedral, trigonal bipyramidal, and octahedral.
By the way, it's page 219.

so my question is......since I can't cheat, I may have to memorize these shapes and angles, am I right?
and If I need to study, how many kinds do I need to know and do I have to memorize both shapes and angles??

 

[ndgurl]

Yes there was a question, yes you should memorize them if you want to be certain to know the answer, no that is not hard to do, and not necessary. If you know the shapes the angles should not be hard to figure out just from looking at the shape. I think the only really important ones though are the ones given in Kaplan. I had two VESPR questions on my exam, only one of which asked for angles. I don't even remember which shape they asked for because it was one of the easy ones that I didn't have to think about much- it might have been trigonal bipyramidal. Know tringonal planar, tetrahedral, linear, octahedral. The other ones can be figured out just by looking at the number of lone pairs. I believe lone pairs always go equatorial, although I could be wrong. I highly doubt you will be asked for angles in one of the ones like t-shaped or seesaw.
Good luck!

Do u guys remember the questions that asks about shapes and angles in Lewis structures? According to my professor, there can be about 12 each.
They are linear, V shaped, bent, trigonal planar, trigonal pyramid, t shaped, tetrahedral, seesaw, trigonal bipyramid, octahedral, square planar, and square pyramid. Their angles are 180, <120, <109.5, 120, <109.5, <90, 109.5, >90, 90/120, 90, 90, >90.

There were questions about these 12 in my class test, and since there are too many, my professor allowed me to use the sheet that has these information.

I just looked at the Kaplan Blue Book, and it only shows 5 different kinds; linear, trigonal planar, tetrahedral, trigonal bipyramidal, and octahedral.
By the way, it's page 219.

so my question is......since I can't cheat, I may have to memorize these shapes and angles, am I right?
and If I need to study, how many kinds do I need to know and do I have to memorize both shapes and angles??

 

[tRNA]

yes I would say definitly memorize them, I kept avoiding them, but I finally memorized them and feel much better