:surprised I know I am overthinking, as always, but for some reason I am just having so much trouble with picturing the 3-d structures (dash/wedge) when solving the problems. My test is tomorrow and I am stuck, I just can't draw them correctly...I get the hybridization, and the angle that will form.(adsbygoogle = window.adsbygoogle || []).push({});

What I don't get is how do you know where to draw a dash or a wedge, and when will the dash be to the upper left corner (extended) versus the lower left? Sometimes they are drawn near eachother (dash and wedge going towards the upper left) with the one in the plane going towards the left. How do you determine this? Does it have to do with the bond angles? I tried figuring it out that way, but I still can't get the right figure without looking at the answer for a hint. For example: (CH3)3 N ... I have no idea how to orient my lewis dot to come up with the right three-d...how do you know which of the hydrogens will be off the plane and et.? Is there a simple way of doing this, and what is wrong with the way I am thinking?

Also, for a positive charged [H2COH] (+) molecule, why is the oxygen atom (as it says in my book) sp2? I know the carbon is sp2, but wouldn't trhe oxygen be sp3 because it's bonded to two things, and it also has 2 pairs of lone electrons?

Any help is greatly appreciated.

Thank you for your help in advance!

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# Homework Help: Trouble with picturing the 3-d structures

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