Difference between Electorn arrangement and VSEPR
Moderators: Chem_Mod, Chem_Admin
-
- Posts: 50
- Joined: Mon Jun 17, 2019 7:22 am
Difference between Electorn arrangement and VSEPR
Hi, does anyone know what's the difference between finding the VSEPR model vs. finding the electron configuration because I'm a little confused. Furthermore, are the shapes of tetrahedral and trigonal pyramid the same, and why are they different from one another? Thank you!
-
- Posts: 55
- Joined: Thu Jul 11, 2019 12:17 am
Re: Difference between Electorn arrangement and VSEPR
The electron arrangement uses the names of VSEPR shapes, but simply denotes where regions of high electron density are found around the central atom. It includes lone pairs into the consideration of the electron arrangement. In contrast, the VSEPR model itself only considers where the atoms are arranged around the central atom, not the lone pairs.
Tetrahedral and trigonal pyramidal are the same electron arrangement because they have 4 regions of high electron density around the central atom. They are, however, not the same VSEPR shape because trigonal pyramidal has 3 atoms around the central atom and 1 lone pair which make up its 4 regions of high electron density.
Tetrahedral and trigonal pyramidal are the same electron arrangement because they have 4 regions of high electron density around the central atom. They are, however, not the same VSEPR shape because trigonal pyramidal has 3 atoms around the central atom and 1 lone pair which make up its 4 regions of high electron density.
-
- Posts: 130
- Joined: Fri Aug 30, 2019 12:16 am
Re: Difference between Electorn arrangement and VSEPR
Electron arrangement takes account for lone pairs to be a region of electron density while molecular shape is only determined by the atoms bonded to the central atom and their bonding regions. Only time electron arrangement and molecular shape are the same is when there are no lone pairs present.
-
- Posts: 50
- Joined: Sat Jul 20, 2019 12:16 am
Re: Difference between Electorn arrangement and VSEPR
finding the VSEPR model is just finding the shape of a molecule, while electron configuration is used for electrons in an atom. tetrahedral and trigonal pyramidal shapes are different. they both have four electron densities surrounding the central atom, but trigonal pyramidal molecules have one lone pair and three bonding pairs. tetrahedral molecules have four bonding pairs.
-
- Posts: 101
- Joined: Fri Aug 02, 2019 12:16 am
Re: Difference between Electorn arrangement and VSEPR
I was confused about this too, but I later realized that the key way to distinguish between the two is that e- arrangement takes into consider the numbers of lone e- pairs and shared e- paired (aka bonds) to determine the name while VSEPR only take into consideration on the number of atoms around the central atom to determine the name.
Re: Difference between Electorn arrangement and VSEPR
There is a difference between the electron configuration of a molecule and the shape of the molecule. While the electron configuration takes lone pairs into accounts as well due to the fact that they are regions of electron density as well, however, the shape of the molecule solely depends on the positions of the atoms because the lone pairs are not visible in the shape of the molecule even though they affect the shape through repulsion. When looking at the electron configuration, we look at the number of regions of electron density so this includes bonding pairs and lone pairs. When drawing the shape of the molecule, however, you will only look at how many of those regions of electron densities are occupied by atoms. For example, an atom that has the 3 bonding pairs and one lone pair has 4 regions of electron density, 3 of which are occupied by atoms. So the electron configuration of this atom will be tetrahedral, but because there are only 3 atoms, so the shape of the molecule is trigonal pyramidal because the lone pair will repel the atoms.
Return to “Determining Molecular Shape (VSEPR)”
Who is online
Users browsing this forum: No registered users and 12 guests