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For questions about polar or non-polar chemical species, or their comparison. Also, for questions where polar or non-polar solvents have an effect.

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Why is the perchlorate anion non-polar?

I just want to confirm that my approach is right. I found that since the hybridisation of this molecule is sp3, the structure is tetrahedral and since all the $\ce{O-Cl}$ bonds are of the same ...
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1answer
182 views

Why does a molecule with a Thiol group form Hydrogen bonds?

I'm doing the GRE Biology practice test, and question #1 asks: The answer is E. I understand why II and IV are polar, but why is $\ce{R-S-H}$ polar? R is a side chain to the sulfur, sulfur's valence ...
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1answer
101 views

Electrode polarity in fuel cells

I am studying fuel cells right now and I'm confused about the polarity of the two electrodes. In the diagram below, the anode is shown as negative. However, why do $\ce{H+}$ ions move away from the ...
3
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1answer
120 views

Why does the C-C bond break earlier than the C-F bond in the pyrolysis of perfluroethane?

According to me $\ce{C-F}$ bond is highly polar and thus is a weaker bond as compared to $\ce{C-C}$. Hence, $\ce{C-F}$ should break first in the pyrolysis of perfluroethane. Instead, in J. D. Lee, it ...
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0answers
50 views

Linalyl acetate: polar or nonpolar? [duplicate]

Why is linalyl acetate nonpolar? From the structure of the molecule I would have assumed that it was polar since it has a $\ce{C=O}$ bond and is asymmetric. What is it that makes it nonpolar?
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1answer
56 views

How does a mostly non-polar molecule prevent a polar head from being pulled off by other polar molecules?

Linear-shaped molecules of a solute with a large non-polar section and a small polar head are not soluble in a polar solvent. Why is this? Why don't the attractive forces between a molecule of polar ...
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0answers
208 views

Why is methamphetamine less polar then amphetamine? [closed]

The question is as stated in the title. Is there a general way to determine relative polarity of organic compounds? This question is for use in the context of the manner in which polarity of the ...
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1answer
285 views

Polarity and acid strength in alcohols

I'm totally confused about the relationship between the polarity and acid strength of a given compoud. Take the case of alcohols itself, it's said that primary alcohols have greater acid strength ...
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1answer
4k views

Halogenation of Phenol [closed]

Why does only one $\ce{Br+}$ ion get generated in a non-polar solvent (such as $\ce{CS2}$), while more $\ce{Br+}$ ions are generated in aqueous or polar solvent (such as $\ce{H2O}$)?
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246 views

Deciding if a molecule is polar and non-polar in cyclic carbon compounds

While discussing about dipole moment of the compounds, our chemistry teacher told that the dipole moment will be 0 for 1,4-Dichlorobenzen, and for those compounds where same atoms or group of atoms ...
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0answers
506 views

Polarity of Acetic Acid, Ethanol and 1-Propanol

In order to compare acetic acid, ethanol and 1-propanol in terms of solubility in hexane, I would like to order them in terms of (a)polarity. By looking up the dipole moments, I found that these ...
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1answer
405 views

Why does an electron-donating group reduce the polarity of the O-H bond? [closed]

Why does the polarity of $\ce{O-H}$ bond decrease if an electron-donating group is attached in the compound? For example, I have seen that when alkyl groups are joined in phenols, the polarity of $\...
2
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2answers
899 views

Why does an OH bond absorb a higher frequency than a CH bond?

I'm wondering why a bond between an O and an H is going to absorb a higher frequency than a bond between a C and an H (any hybridization). O is heavier than C in terms of atomic masses, and I'm ...
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2answers
297 views

Hartree-Fock dipole moment

I read this sentence in a paper (J. Phys. Chem. A 2014, 118 (20), 3678–3687. DOI: 10.1021/jp502475e): Calculations using Hartree–Fock theory systematically overestimated dipole moments and ...
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0answers
1k views

Why do chloroform and benzene exhibit negative deviation from Raoult's law?

Chloroform is a polar molecule, and benzene is nonpolar. Shouldn't the chloroform-chloroform and benzene-benzene intermolecular forces be stronger than chloroform-benzene interactions (like dissolves ...
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1answer
203 views

Polarity of symmetric Lewis structure [closed]

Why is $\ce{CF2Cl2}$ polar? The Lewis dot structure shows the molecule as being symmetric. Wouldn't that make it nonpolar?
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1answer
228 views

Affinity to mobile or stationary phase during column chromatography [closed]

I have carried a column chromatography and obtained two compounds. The first one is liquid (ester) and the second one is solid (nitro) yet I know that the second compound is less polar than the first ...
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2answers
467 views

Mechanism of Halogenation of Alkene

In the above reaction, we use a non-polar compound (such as CCl$_4$) as a solvent. Then, why does the Br$_2$ polarise on attack by the alkene, even though a non-polar solvent does not encourage ...
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0answers
86 views

What makes a bond non-polarisable?

Many chemical bonds are known to be polarisable. Similarly, many ions are also known to be polarisable. Examples include the carbon-iodine bond and the carbonate ion. Recently, I have read that the ...
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0answers
53 views

Why is the molecular dipole the main determinant of whether a substance dissolves in another substance?

Consider a covalent molecule such as carbon tetrafluoride. In $\ce{CF4}$, each $\ce{C-F}$ bond is polar covalent. However, this substance is considered overall non-polar because each bond dipole ...
4
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2answers
3k views

Why does acetone have a greater dipole moment than dimethyl ether?

Below are the lewis structures for dimethyl ether and acetone. My chemistry textbook indicates that acetone has a larger dipole moment than dimethyl ether. I am familiar with dipole moments and the ...
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40 views

Ionic or Covalent? [duplicate]

Is BeF2 ionic or covalent? BeF2 : covalent or ionic? The above link does not provide a proper explanation as to why it should be ionic, even though fluoride anion is large and polarisable and ...
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0answers
235 views

Mixing solvents of different polarity [closed]

Suppose a non-polar solid is dissolved in ethanol. Water is added to the solution. Will the solid separate, if it isn't soluble in water?
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1answer
930 views

How does HCl dissolve in water if the intramolecular force is stronger?

So what I know now is that the H in HCl is more positive and the Cl is more negative, while the H in H2O is more positive and the O is more negative. When HCl enters water, its more positive atoms (H) ...
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3answers
3k views

What determines “polarizability” of an element?

In this question, the answer given discusses that fluorine has a good orbital overlap with hydrogen and also that fluorine is not very polarizable. However, is it always true that strong bonding is ...
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4answers
898 views

Easiest way (software) to visualize charge density from an .xyz file with point-charges?

I have an .xyz file which contains partial charges calculated by a Quantum-Chemistry software (NWChem). The system looks like this, here I show the partial charges calculated from the electrostatic ...
1
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1answer
935 views

Polarity of xenon fluoride

The structure of xenon fluoride is a capped octahedron. The lone pair is stereochemically active, i.e. it will rotate about. The dipole moments of the axial fluorides will get cancelled, and so will ...
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0answers
253 views

Enthalpy of dissolution and how well it dissolves - Gibbs free energy as well - polarity

I've been researching on this topic, and I am not sure that I have got it right. From what I've read, I believe that the more exothermic the enthalpy of solution is, the more likely it is to be ...
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0answers
93 views

Why does increasing electronegativity difference result in decreasing density?

I've been collecting data and there's a very strong inverse relationship between electronegativity difference and density ($\pu{R^2}$ value of roughly 0.95 from my data). Is there any chemistry that ...
14
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2answers
924 views

Why are dipoles “permanent/induced dipole permanent/induced dipole” and not just “permanent/induced dipole” once?

My teacher would always say "induced dipole induced dipole" and while it annoyed my slightly (as you were saying the same word twice) it didn't really bother me, ...
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1answer
468 views

Can I use gasoline as a non-polar solvent?

I was wondering if I can use gasoline for a non-polar extraction of organic substances instead of prescribed diethyl ether, which is a bit hard to get in my country. If not, are there any products ...
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0answers
272 views

Overall polarity of polychlorinated benzofuran

I have been struggling over this weekend to find an answer for the overall polarity of this molecule: 2,3,7,8-tetrachlorobenzofuran In order to find intramolecular forces, I determined the difference ...
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2answers
2k views

Why is sodium carbonate less soluble in water than sodium bicarbonate?

Why is sodium carbonate less soluble in water than sodium bicarbonate? If you think about their structures, the only thing that is different is that sodium carbonate has two sodium atoms, while sodium ...
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1answer
502 views

What causes polarization in noble gases?

According to my knowledge, polarization occurs when in a compound there is a difference of polarity its constituents. But in the case of noble gases, there is a single component. What exactly is ...
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3answers
6k views

Why are some molecules unable to absorb Infrared radiation?

$\ce{CH4}$ is symmetrical and non polar and so is $\ce{O2}$ but $\ce{O2}$ doesn't absorb IR. Why is that? People say that if a molecule can change its polarity then it will absorb IR but I don't ...
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1answer
195 views

Why is Cyanidine soluble in water?

Cyanidine is not polar due to its make-up of only hydrogen atoms and carbon atoms, correct? But "like dissolve like", which means it would HAVE to be polar, or no? Is it then soluble solely because of ...
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1answer
4k views

How to determine relative polarity (basic procedure)? [closed]

I am taking AP Chemistry, and have noticed that I can identify a polyatomic polar molecule, but struggle to determine which molecule is the most polar given a set of several polar molecules. What ...
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0answers
433 views

What is the need for dipole moment if electronegativity already exists?

Say we have an HCl molecule. The difference in electronegativities of the H and Cl atoms tells us how polar the HCl molecule is. The dipole moment is also a measure of the degree of polarity in ...
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1answer
1k views

Polarity and stability

Why is cis-1,2-cyclohexadiol less polar than trans-1,2-cyclohexadiol? I know it has something to do with stability and chair conformations, but I'm not sure how it relates to polarity. I know cis-1,...
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0answers
65 views

Supercritical fluids polarity

Water is a polar solvent, but in the supercritical fluid state, it is much less polar, I presume because of the cleavage of hydrogen bonds. On the other hand, carbon dioxide is non-polar, but as a ...
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2answers
114 views

Why is a cationic trialkylammonium functional group inductively withdrawing in nature?

The alkyl groups on the nitrogen ion should donate electrons (alkyl groups are electron donating in nature). So, irrespective of the nitrogen ion being a cation (which is an electrophile), the alkyl ...
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1answer
318 views

Why is arsenic trichloride more likely to be polar than aluminum trichloride?

According to my chemistry teacher, $\ce{AsCl3}$ is more likely to be polar than $\ce{AlCl3}$. Why is this? As I understand it, the difference in electronegativity is what makes a compound more or less ...
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0answers
907 views

polar covalent bond

Please take a look at the image of polar covalent bond in the $\ce{H2O}$ molecule below. My question is given in bold type in the following discussion. Here is my flow of thought that confused me so ...
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1answer
6k views

What is the most polar covalent bond?

Which polar covalent bond of the following: Cl-F S-O P-N C-Cl It's trivia - I guess. And I got it wrong. Electronegativity list was given for the following: F, O, Cl, N, S, C, H, P My wrong ...
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1answer
911 views

When would the presence of lone pair result in a polar molecule?

In what cases would the presence of a lone pair result in a polar molecule? For instance, O3 is polar despite only consisting of O atoms due to the presence of lone pair of electrons. However, O2 also ...
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1answer
236 views

How Can an Amino Acid Be Non-Polar?

Looking at the structure of an amino acid (as a zwitterion), it seems that the part of the molecule with the amino group and the carboxylic acid group are quite polar (the amino group has a positive ...
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1answer
999 views

Why are alkyl halides used as solvents for relatively non polar compounds and not polar compounds?

It is written in my textbook that : Alkyl halides are used as solvents for relatively non polar compounds. Alkyl halides are themselves polar with carbon having delta positive charge and halide ...
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1answer
8k views

How to determine the order of elution in silica gel column chromatography?

Benzofuranoids ustusoranes A (1), B (2), and E (3) were isolated from Aspergillus ustus 094102. If these compounds were separated by column chromatography on silica gel, what would be the elution ...
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1answer
10k views

Do polar compounds travel further or less far than unpolar ones in hexane/ethyl acetate TLCs?

Would ethyl acetate/hexane be considered nonpolar or polar overall? I know that the ethyl acetate is polar and the hexane is nonpolar. I am trying to understand what if polar or nonpolar analgesics ...
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1answer
224 views

Polar/ non-polar nature of HgI2

Is $\ce{HgI_2}$ polar or non-polar? The electronegativity difference between Hg and I is about 0.66, so the compound should be almost covalent. However, I cannot find the structure of $\ce{HgI_2}$ as ...