## Bond Angle

(Polar molecules, Non-polar molecules, etc.)

Enzo_1I
Posts: 19
Joined: Fri Apr 06, 2018 11:02 am

### Bond Angle

How do I determine bond angle for a molecule?

Sunjum Singh 1I
Posts: 30
Joined: Fri Apr 06, 2018 11:05 am

### Re: Bond Angle

Lavelle said in lecture that we don't need to know the exact value of the bond angles since they are experimentally calculated.

Liliana Rosales 1E
Posts: 36
Joined: Wed Nov 15, 2017 3:03 am

### Re: Bond Angle

If you know the shape of the molecule, then you can know the bond angles. For example, tetrahedral molecules, have bond angles of 109.5°. Just know the bond angles for each of the shapes Lavelle went over in lecture.(Linear, trigonal planar, tetrahedral,octahedral and so forth)

Shimran Kumar 1C
Posts: 30
Joined: Fri Apr 06, 2018 11:03 am

### Re: Bond Angle

Linear: 180°
Trigonal planar: 120°
Tetrahedral: 109.5°

You can look at the shape of the molecule and estimate the bond angles based on these values. For example, if the bond angles look smaller than the bond angles of trigonal planar, then you would say "less than 120°".

Jacob Samuels 1E
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Joined: Fri Apr 06, 2018 11:05 am

### Re: Bond Angle

Will we have to memorize all the bond angles for the final?

Vienna Cimetta 1L
Posts: 31
Joined: Thu Feb 01, 2018 3:01 am

### Re: Bond Angle

I'm pretty sure you just have to memorize the bond angles are this point. Some are straight forward, like when you see a linear structure you know its 180, but other than that I think its just best to memorize the odd ones like when its less than 109.5. Also some structures will have more than one bond type.

Chem_Mod
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### Re: Bond Angle

You do need to memorize the general bond angles that certain number of regions of electron density give rise too. You do need to know how the lone pair electrons will affect the angles too.