determining molecular shape

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

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Agustina Santa Cruz 2F
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determining molecular shape

Postby Agustina Santa Cruz 2F » Fri Nov 20, 2020 2:57 pm

How is Co2 not polar but So2 is? Since they both have similar structures.

Chem_Mod
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Re: determining molecular shape

Postby Chem_Mod » Fri Nov 20, 2020 3:13 pm

The central atom in CO2 does not have a lone pair, while the central atom in SO2 does. Due to the presence of the lone pair, SO2 will be polar.

Austin Aldujaili 2D
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Re: determining molecular shape

Postby Austin Aldujaili 2D » Fri Nov 20, 2020 3:18 pm

SO2 can have an expanded octate since some of its valence electrons are in the 3d orbital. That means it will have a lone pair to satisfy all the electrons in the molecule. Lone pair makes it polar versus CO2 has only 4 bonds with the two 0xygen molecules, no lone pairs.

Katie Nye 2F
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Re: determining molecular shape

Postby Katie Nye 2F » Fri Nov 20, 2020 3:45 pm

CO2 is nonpolar because it is symmetrical and has no lone pairs. The lone pair on the S atom in SO2 distorts it and repels the atoms down into a bent molecular shape.

Sabine Salvucci 2E
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Re: determining molecular shape

Postby Sabine Salvucci 2E » Fri Nov 20, 2020 4:28 pm

Hello! Since CO2 does not have a lone pair on the central atom, its shape is linear. However, since SO2 does have a lone pair on the central atom, its shape is bent. This happens because the lone pair basically repels electrons from the other bonds. Since CO2 is linear and symmetrical it is non polar, but since SO2 is bent and asymmetrical, it is polar. Hope this helps!

Evelyn Silva 3J
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Re: determining molecular shape

Postby Evelyn Silva 3J » Fri Nov 20, 2020 5:57 pm

The lone pair in the SO2 atom repels the O atoms down, giving the molecule a bent shape. Looking at the vectors, you will see that the molecule is polar. In CO2, however, Carbon does not have a lone pair, so the molecule is linear and nonpolar.

BrittneyMyint1D
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Re: determining molecular shape

Postby BrittneyMyint1D » Fri Nov 20, 2020 7:00 pm

Hi, as everyone has said, the Lewis structures of CO2 and SO2 show that the central atom in CO2 does not have a lone pair while the central atom of SO2 does. So, the lone pair on the S atom causes lone pair and bonding pair repulsion, making SO2 have a bent shape. If you draw the vectors, you find that the vectors on SO2 do not cancel out, so SO2 is polar. CO2 has a linear shape, so when you draw its vectors, they cancel out, so CO2 is nonpolar. Hope this helps!

Jiapeng Han 1C
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Re: determining molecular shape

Postby Jiapeng Han 1C » Sat Nov 21, 2020 4:03 am

Although CO bond is polar, CO2 molecule is linear in shape so that the dipoles cancel out. For SO2, it has two SO double bond and a lone pair on S atom. As a result, the shape is bent so that the dipoles can't cancel out.

Pranav Daggubati 3C
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Re: determining molecular shape

Postby Pranav Daggubati 3C » Sat Nov 21, 2020 10:59 am

CO2 is a linear molecule, so the dipoles between the carbon and oxygens cancel out. SO2 is a trigonal planar molecule, so the S=O bonds don't cancel out.

jessicasilverstein1F
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Re: determining molecular shape

Postby jessicasilverstein1F » Sat Nov 21, 2020 11:30 am

The reason for this is that there is a lone pair on the S atom in SO2. This then distorts the molecule and repels the atoms down into a bent molecular shape

Nhu Pham-Dis3G
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Re: determining molecular shape

Postby Nhu Pham-Dis3G » Sat Nov 21, 2020 4:29 pm

Co2 is nonpolar because its dipole moment is 0 and the shape is also linear. When looking at the entire molecule, we can see that Co2 has a net moment of 0.


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