AX3E
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Re: AX3E
It would be trigonal pyramidal since there is a lone pairs of electrons on the central atom in a tetrahedral arrangemen
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Re: AX3E
If you imagine this in 3D space, you can see that it is trigonal pyramidal tetrahedral. It is easy to confuse this with it being bent but be careful not to make that mistake.
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Re: AX3E
In order to really break this down to know that it is trigonal pyramidal, you must understand the notation used in VSEPR Model.
A is the central atom X is the number of bonded atoms E is the number of lone pairs
One example of a trigonal pyramidal shaped molecule is NH3.
N is the central atom, therefore A
There are 3 bonded atoms to N, 3 H atoms, therefore X3
There is one pair of lone pairs on top of the N, therefore E
A is the central atom X is the number of bonded atoms E is the number of lone pairs
One example of a trigonal pyramidal shaped molecule is NH3.
N is the central atom, therefore A
There are 3 bonded atoms to N, 3 H atoms, therefore X3
There is one pair of lone pairs on top of the N, therefore E
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Re: AX3E
The electron arrangement would be tetrahedral, however since one is a lone pair the shape is trigonal pyramidal.
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Re: AX3E
First, add together the number of bonds in the molecule (the number following X). In this case, it is 3. Then add the number of lone pairs (the number following E). In this case, it is 1. 3 + 1 = 4. Therefore, we know that the shape is tetrahedral, but since there is a lone pair, the geometry is trigonal pyramidal.
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Re: AX3E
kevinav wrote:What would be the molecular shape for the general formula AX3E
The molecule would have a trigonal pyramidal molecular shape.
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Re: AX3E
First, look at the steric number of the lewis structure, which is 4 (there are 4 regions of electron density). Then look at the surrounding atoms to the central atom. The subscript following the X in the VSEPR formula indicates that there are 3 surrounding atoms. Lastly, look at the number of lone pairs attached to the central atom. The subscript to E is 1 (most times invisible), which tells us that there is only one lone pair. From here we can determine that though the shape of a structure with 4 regions of electron density would be tetrahedral, AX3E is trigonal pyramidal due to the lone pair repulsion.
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Re: AX3E
The shape is trigonal pyramidal and you base it off of the original tetrahedral shape, for once you remove a bond and add an electron pair to tetrahedral, it becomes trigonal pyramidal.
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