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27 votes

Is the carbon atom in the carbon dioxide molecule partially positive?

You're correct in assuming that the carbon atom in $\ce{CO2}$ has a partial positive charge. This is because the oxygen atoms are much more electronegative, so they pull the electrons away from the ...
mpprogram6771's user avatar
21 votes
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Is dipole moment a vector?

we assume for no particular reason that dipole moments must be behaving like vectors Ah, but there is a reason. Consider the interaction of a molecule with the scalar potential $$ E_{\text{int}} = \...
pentavalentcarbon's user avatar
18 votes

Is the carbon atom in the carbon dioxide molecule partially positive?

The other answers have done a great job explaining why, even though its bonds are polar, $\ce{CO2}$ lacks a permanent dipole: the molecule's symmetry cancels out the polarity of its bonds. But that's ...
theorist's user avatar
  • 12.1k
17 votes

Is Hexafluorocyclohexane the "Most Polar" Small Molecule?

At first I checked common organic compounds and solvents in CRC Handbook [1, 9-59] that have dipole moment above $\pu{4.5 D}$: \begin{array}{llrr} \hline \text{Name} & \text{Formula} & \text{...
andselisk's user avatar
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17 votes
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Why is the dipole moment of chloromethane larger than the dipole moment of fluoromethane?

Dipole moment is not just about charges, it also has $L$ term. Bond length of $\ce{C-Cl}$ is greater than $\ce{C-F}$ and in this case, that is more dominating factor. The dipole moment is in order ...
Black Jack 21's user avatar
15 votes

Why do post-Hartree-Fock methods fail to predict the direction of the dipole moment of carbon monoxide?

The question itself is void, as all methods with the exception of Hartree-Fock predict the direction of the dipole moment correctly. Deathbreath found a Full CI calculation in Jeremy P. Coe, Daniel J. ...
Martin - マーチン's user avatar
15 votes
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How to identify hydrogen bonds and other non-covalent interactions from structure considerations?

It is safe to say that there will always be intermolecular forces at play. At the time where you will consider these you should already have a good idea about the molecules involved in your system. ...
Martin - マーチン's user avatar
15 votes
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Why does C=O have a larger dipole moment than C-O?

According to Wikipedia, bond dipole moment depends on: Distance between atoms and Overall charge difference, not just electronegativity difference. Resonance tells us that there is some amount ...
Dennis Cao's user avatar
15 votes

Is the carbon atom in the carbon dioxide molecule partially positive?

You are correct, the carbon does have a positive charge. We cannot measure a dipole, but that doesn't prove anything. However, $\ce{CO2}$ does have a quadrupole moment. Imagine a $\ce{CO2}$ molecule ...
MSalters's user avatar
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15 votes
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Dipole moment of (1s,2s,3s)-1,2,3-trichlorocyclopropane

The issue stems from the fact that you may not have understood what each bond notation means. Here, the solid wedge indicates that the bond is toward us and so a 3-D view of the same molecule would ...
Safdar Faisal's user avatar
14 votes

Confusion about direction of dipole arrow in alpha-helices and other molecules

I (accidentally) stumbled upon the following statement in Atkins' "Elements of Physical Chemistry" (p378): We represent dipole moments by an arrow with a length proportional to $\pmb{\mu}$ and ...
Martin - マーチン's user avatar
14 votes
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Why are dipoles "permanent/induced dipole permanent/induced dipole" and not just "permanent/induced dipole" once?

Because it takes two to tango. Dipoles interact with each other. A Lone dipole has nothing to interact with (other than an electric field, but if we ignore some externally applied macro field, there ...
matt_black's user avatar
  • 35.9k
14 votes
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Differences between formulae for dipole–dipole interaction energy

They are both dipole-dipole energies as from the link but their contexts are different. Eq. 3 (as numbered in the LibreTexts link), $$V(r) = - \frac{\mu_{1}\mu_{2}}{4\pi\epsilon_{0}r^{3}} \tag{3}$$ is ...
Unskilled's user avatar
  • 371
13 votes

Is the carbon atom in the carbon dioxide molecule partially positive?

The previous answers by mpprogram6771 and MSalters nailed it. I'd like to add that, as $\ce{CO2}$ is a very small molecule, you can, with a bit of effort, set up a little numeric experiment to answer ...
ksousa's user avatar
  • 663
12 votes
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What is the origin of the "positive-to-negative" convention concerning dipole moments in chemistry?

Some sources point out the direction of the dipole moment is convention dependent. Since both conventions are mathematically correct it seems important when solving a problem to identify the ...
Agriculturist's user avatar
12 votes
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What is the dipole moment direction in the nitrosonium ion?

In non-neutral species the dipole moment in calculations is dependent on the choice of the co-ordinate system. For this reason the origin is chosen to be the centre of mass. With $r=107.8~\pu{pm}$ on ...
Martin - マーチン's user avatar
12 votes
Accepted

How do atoms lose their induced dipole?

The said lesson tends to oversimplify things to the point of getting them downright wrong. Atom dipoles do not line up with each other. They are way too weak for that. Should it be according to your ...
Ivan Neretin's user avatar
  • 31.2k
11 votes

Is Hexafluorocyclohexane the "Most Polar" Small Molecule?

Calicene ($4.66~\pu{D}$, 14 atoms) and its derivatives are also good candidates. For Hexaphenylcalicene, a hydrocarbon with 74 atoms, a dipole moment of $6.3~\pu{D}$ has been reported.[1] 2,3-dicyano-...
aventurin's user avatar
  • 7,170
11 votes
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How do you calculate the dipole moment of larger molecules?

The total dipole of a molecule can be thought of as the sum of dipoles of individual functional groups: $$ \vec{\mu}_{\text{total}} = \sum_{i}^{N_\text{groups}} \vec{\mu}_{i} $$ Because each dipole ...
pentavalentcarbon's user avatar
11 votes

What is the exact reason that compounds such as carbon dioxide cannot interact with other compounds through dipole-dipole interactions?

As the other answers have indicated, CO2 has no NET dipole moment. However it does have two dipoles pointed in opposite directions (as OP keeps mentioning). This means that CO2 can possibly interact ...
user157879's user avatar
11 votes

Why does p-dichlorobenzene have zero dipole moment while hydroquinone does not?

To facilitate this discussion, here are the two structures. You may remember from the beginning of organic chemistry classes that free rotation can occur around single bonds. This is mostly taught ...
Jan's user avatar
  • 67.8k
11 votes
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Calculating dipole moments from atomic partial charges

From a theoretical standpoint, that approach is correct: $$ \mu_i = \sum_{a}^{N_{\text{atoms}}} \sum_{i\in\{x,y,z\}} r_{ia}q_{a}, $$ where the set of atomic partial charges $\{q\}$ could come from ...
pentavalentcarbon's user avatar
11 votes

Differences between formulae for dipole–dipole interaction energy

An equivalent and easier formula when a molecule's coordinates are known is to use vectors. The energy is then $$V=\frac{1}{4\pi\epsilon_0}\left(\frac{\vec\mu_1\cdot\vec\mu_2}{r^3}-3\frac{(\vec\mu_1\...
porphyrin's user avatar
  • 30.3k
10 votes
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Does 1-bromo-4-chlorobenzene have a permanent dipole moment?

As others have stated before in the comments, the molecule itself has a dipole moment, but it is indeed very, very small, to the point where you would say it is negligible. To illustrate this, I have ...
Martin - マーチン's user avatar
10 votes
Accepted

Why does ozone have a dipole moment different than 0

The electrons are not shared equally among the oxygen atoms. The central oxygen atom alone donates three electrons to the covalent bonding whereas the other two oxygen atoms combined donate the other ...
Oscar Lanzi's user avatar
  • 55.9k
9 votes

What is the exact reason that compounds such as carbon dioxide cannot interact with other compounds through dipole-dipole interactions?

Carbon dioxide is more than linear. It's symmetric, and the axis of symmetry perpendicular to the bonds also applies to whatever dipole moment it has. The only vector that looks the same after being ...
Zhe's user avatar
  • 17.4k
8 votes
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What are dipole moments in a molecule supposed to act upon?

Your confusion appears to arise from trying to consider dipole vectors as representing forces, which is incorrect. Dipole vectors don't "act on" anything; they describe the displacement of the "...
hBy2Py's user avatar
  • 17.3k
8 votes
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Polarity index vs. Dipole moment

From Roger E. Schirmer "Modern Methods of Pharmaceutical Analysis": Solvents are generally ranked by polarity, but polarity is not a uniquely defined physical property of a substance. Hence the ...
CoffeeIsLife's user avatar
  • 4,284
8 votes

What is the exact reason that compounds such as carbon dioxide cannot interact with other compounds through dipole-dipole interactions?

Exactly that. Dipole-dipole interactions are caused because the positive end of one dipole is attracted to the negative end of another dipole. This macroscopic attraction can only occur if the centre ...
Jan's user avatar
  • 67.8k

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