Bond Angels
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Bond Angels
I still don't quite understand how bond angles are found. Can someone explain how to solve for them?
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Re: Bond Angels
Bond angles are formed when electron pairs repel each other. The electron pairs will assume a geometry that keeps them as far apart from each other as possible because of this repulsion.
Re: Bond Angels
We can determine bond angles using the VSEPR theory. Because of electron repulsion, molecules form shapes that will give them the lowest repulsion energy.
The basic idea, though, is to look at how many bonds a central atom forms and how many lone pairs surround it. (In this case triple bonds and double bonds don't count for more than a single bond because they are just blobs of electron density)
In water, there are two bonding pairs and two lone pairs. This gives the molecule a bond angle of about 105 degrees and a bent shape.
The chart in section 2E of the 7th edition really helps, but the bond angles and shapes are just something we have to memorize.
The basic idea, though, is to look at how many bonds a central atom forms and how many lone pairs surround it. (In this case triple bonds and double bonds don't count for more than a single bond because they are just blobs of electron density)
In water, there are two bonding pairs and two lone pairs. This gives the molecule a bond angle of about 105 degrees and a bent shape.
The chart in section 2E of the 7th edition really helps, but the bond angles and shapes are just something we have to memorize.
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Re: Bond Angels
Bond angles are the angles that are created by electrons. Since they are the same negative charges, they repel and that creates a bond. For example, a central atom bonded by two other atoms creates a linear bond. Electrons are so repulsed by one another, they want to remain as far apart from each other as possible, often making symmetrical shapes on 2D surfaces as well as symmetrical shapes in 3D surfaces. This causes bond angles to be the same and 3D shapes can have multiple angles. You can assume one's shape by their bond angles and how many atoms they are bounded to. I hope this helps! The chart below is also a great resource.
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Re: Bond Angels
Will molecules of the same shape always have the same bond angles? Like will all tetrahedral molecules etc have the same angles regardless of the molecule?
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Re: Bond Angels
Jennifer Lathrop 3E wrote:Will molecules of the same shape always have the same bond angles? Like will all tetrahedral molecules etc have the same angles regardless of the molecule?
Hypothetically, Molecules of the same shape would have the same bond angles since shape/ molecular geometry is what we use to predict the angles. However, experimentally I would think they would be different just like our predictions aren't always spot on.
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