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Electronegativity - Polarity ( Bond Angles)

I really don't understand how you would draw the molecules e.g different lines for example the ones that have bond lines and the ones that come out the paper etc... how do you know which lines to use .Also how do you know which angles to use ? Thanks
Original post by nisha.sri
I really don't understand how you would draw the molecules e.g different lines for example the ones that have bond lines and the ones that come out the paper etc... how do you know which lines to use .Also how do you know which angles to use ? Thanks


Original post by Kvothe the Arcane

Legit. Takes practice. It's hard to symbolise 3D structure on 2D paper.Just have to get used to the narrative
Original post by Kvothe the Arcane


But how do you know which to use and how the structure will look like ? Sorry i missed a lesson and i'm clueless

Original post by 303Pharma
Legit. Takes practice. It's hard to symbolise 3D structure on 2D paper.Just have to get used to the narrative
Original post by nisha.sri
But how do you know which to use and how the structure will look like ? Sorry i missed a lesson and i'm clueless

Try molecular modelling kits. Like https://www.amazon.co.uk/Koly-Scientific-Inorganic-Chemistry-Molecular/dp/B01DDJ4CXU/ref=sr_1_6?ie=UTF8&qid=1475311529&sr=8-6&keywords=chemistry+balls

Helps visualisation.
Original post by 303Pharma


I mean how do you know how to draw different molecules ? And how do you know what angles to use ?
Are you familiar with VSERP?
Original post by nisha.sri
I mean how do you know how to draw different molecules ? And how do you know what angles to use ?



Just draw the bonds spaced evenly around the atom, and coming in or out if nessecary.
Angle depends on number of pairs of electrons (lone pairs repel more by 2.5 degrees)
2 pairs = 180
3 pairs = 120
4 pairs = 109
6 pairs = 90
(edited 7 years ago)
Original post by james813
Just draw the bonds spaced evenly around the atom, and coming in or out if nessecary.
Angle depends on number if pairs of electrons (lone pairs repel more by 2.5 degrees)
2 pairs = 180
3 pairs = 120
4 pairs = 109
6 pairs = 90

Math Geek got activated please don't do that. Can you explainer in more detain?. .
Original post by 303Pharma
Math Geek got activated please don't do that. Can you explainer in more detain?. .


So you want to find a bond angle, first count how many electron pairs around the central atom. Then use the corresponding angle above. If there are both lone pairs and bonding pairs, each bonding pair will repel less by 2.5 degrees. Hope that helps.
Original post by james813
So you want to find a bond angle, first count how many electron pairs around the central atom. Then use the corresponding angle above. If there are both lone pairs and bonding pairs, each bonding pair will repel less by 2.5 degrees. Hope that helps.


Ah thanks :smile: Can you give me an example :smile:
I used to always get muddled up with this and still do. Especially when drawing mirror images etc :frown:
Original post by 303Pharma
Are you familiar with VSERP?


No what's that ?
Original post by nisha.sri
Ah thanks :smile: Can you give me an example :smile:



No, but Google can.
Original post by nisha.sri
No what's that ?
Google search. Like two seconds. You dint't hit an answer?
Original post by nisha.sri
No what's that ?
Valence Shell Electro Repulsive Theory. It's the standard model for describing, at the molecular level, the shape and structure of atomic / molecular bonds.
bnmbnm

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