Questions tagged [polarity]
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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Iodine monochloride (I-Cl) bond cleavage issue
During an electrophilic addition of iodine monochloride $(\ce{ICl})$ with alkene, the $\ce{I-Cl}$ bond cleaves as $\ce{I+}$ and $\ce{Cl-}$. Then $\ce{I+}$ attacks the double bond, and later $\ce{Cl-}$ ...
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What is the actual relationship between partition coefficient (logP or clog P) and Retention factor (Rf) value?
I have been wondering for a long time if there is any software or website that can predict the Rf value of a molecule based on its molecular structure (more so, because I was unable to figure out ...
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Can we decouple electrostatic force from hydrogen bonds?
The nature of hydrogen bonds is an intriguing question. According to this post, hydrogen bonds are made primarily of electrostatic force with a small contribution of electron transfer to the ...
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Order of Polarities/Dipole Moments of CH3F, CH3Cl, CH3Br and CH3I [duplicate]
While explaining how to decide polarities/dipole moments of molecules, my teacher highlighted an exception to the statement:
For similar compounds like hydrides formed by different elements of a ...
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Polarized Bond and Bond Strength Relationship
So more polarized bonds are generally stronger ($\ce{C-O}$ bond energy $> \ce{C-C}$ bond energy), but more polarized bonds are also more reactive... is this something to simply accept?
So, taking ...
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Is electroplating possible in a solvent that doesn't dissociate precursor molecules?
There are metalorganic compounds, soluble in nonpolar solvents without dissociation into ions. Is it possible, in some rare cases, to apply voltage to submerged electrodes so that it causes the ...
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Reasons of ethanol's and ethanethiol's complete solubility and low solubility in water respectively
Suggest an explanation for the observations that ethanol($\ce{C_2H_5OH}$), is completely miscible with water and that ethanethiol ($\ce{C2H5SH}$) is soluble only to the extent of 1.5 g per 100 mL of ...
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Cyclodextrins: Is there really a hydrophobic interior and hydrophilic exterior?
I do not get most of the explanations on why cyclodextrins are so good at hosting hydrophobic molecules. It is true that the hydroxyl groups are pointed outwards and thus the cavity is definitely less ...
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Mobility of salts on unbonded bare silica HILIC column
I have two chemical compounds that I put on cells, to see if they can diffuse into the cytosol. The compounds are similar in structure, but contain a key modification that alter the polarity ...
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Polarity of caffeine [closed]
I have to submit an investigatory project for my Ochem exams and I chose to write up a report on quantitative analysis of caffeine in different tea samples. During Extraction of caffeine, we use ...
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Why DMSO has much higher freezing point than DMF (19 °C vs -61 °C)?
Recently, while solvent optimization of a reaction, I found DMSO froze in an ice-bath but DMF didn't.
From Wikipedia, I found out that DMSO (dimethyl sulfoxide) has a freezing point of 19 °C (ref. 1) ...
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Degradation via electrolysis and electrode surface area
What is the relationship between electrode surface area and processes such as electrolysis/electrode polarization?
Let's say for example I want a fixed electric field between two electrodes in a ...
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TLC experiment interprentation
I am having difficulty interpreting the results of an identification test involving six different standards (dyes) in an unknown mixture of dyes, using silica gel TLC plates and acetone as the mobile ...
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Solubility of alkanes in benzene [duplicate]
According to “like dissolves like” rule of thumb, a homogeneous (true) solution forms between:
polar solvent and polar (ionic) solutes;
non-polar solvent and non-polar (covalent) solutes.
According ...
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Which one has a greater dipole moment: benzamide or benzoic acid?
My guess is that, since the relative electronegativities are similar, therefore the difference would arise only due to magnitudes of difference in electronegativities. And hence the strength should be ...
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Question on electron density
I was working with ammonia ($\ce{NH3}$) and phosphine($\ce{PH3}$). Both have lone pair electron. But $\ce{NH3}$ is stronger base (Lewis base) than $\ce{PH3}$.
I was told by my instructor that it is ...
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Is a microplastic saturated ferrofluid polar or nonpolar? [closed]
In my experiment (Junior science fair) I submerged a magnetic chip collector holding my ferrofluid (magnetite and grape seed oil) with polypropylene beads (attracted as part of the experiment) into ...
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Can “hydrates” of crystals form with other molecules?
It is well known that copper sulfate, sodium sulfate, et al crystallize with 5,10 water molecules of hydration, locked in their crystal lattices. Is it possible to have other molecules instead of ...
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How does polarity increase when electron density in oxygen decreases when comparing acidity
My book says the following statement:
Due to the higher electronegativity of $sp^{2}$ hybridized carbon of phenol , the electron density in oxygen decreases. This increases polarity of O-H bond and ...
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Can we mix non polar and polar molecules by providing heat? [closed]
Polar molecules don't dissolve with non polar molecules because of difference in forces of attraction between them. But if we provide enough heat will they mix?
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Does an ionic bond have a dipole?
Is an ionic compound like NaCl considered a dipole? It has a positive side (Na+) and a negative side (Cl-). Or is it true that an ionic bond does not have a dipole because a dipole is, by definition, ...
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Relative polarity - definition and meaning
I am struggling with understanding the parameter called "Relative Polarity" (RP). I know it is supposed to be an arbitrary scale, but I fail to grasp what the values represent. I understand ...
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HPLC Solubility vs polarity
According to this data collected from PubChem, polarity of nitrobenzene and benzonitrile should be similar since solubility is dependent on the polarity:
Nitrobenzene: Solubility in water, 0.2 g/100ml
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Polarity and solubility
I have a doubt about solubility: a molecule is polar when it has a dipole moment that is ≠ 0. Very often it is said that like dissolves like, that is, that polar substances dissolve in polar solvents, ...
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What happens if you carbonate ethanol?
The electronics youtuber bigclivedotcom has an on-and-off-again series where he carbonates various types of alcohol and comments on the taste. One thing he's noticed is that the stronger the alcohol, ...
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How do solutions act as solvents?
For example:
Silver chloride, $\ce{AgCl}$, dissolves in dilute aqueous ammonia, so this can be used in qualitative analysis, after reacting $\ce{Ag+}$ ions with $\ce{Cl-}$ ions, to differentiate the ...
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How does the branched structure of glycogen, increase its ability to be hydrolysed?
"Glycogen branching is essential because it allows for increased water solubility and several sites to break it down; this allows for easy and quick glycogen utilization when it is broken down&...
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Air/Acetonitrile Interfaces
Say I drop some acetonitrile on a grounded surface and it forms a meniscus. The acetonitrile is in air. Lets forget about evaporation for the moment.
Will there be an interfacial dipole formed by the ...
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Can Polarizing Power and the Inductive Effect both explain the highly covalent bonds of Mn2O7?
The Mn-O bonds of Mn2O7 have more covalent character than those of MnO2. This makes sense when imagining Mn2O7 to consist of Mn7+ ions and O2- ions; the high charge of the cations give them a high ...
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In acids why does polarising the O-H bond weaken rather than strengthen it?
In hexaaquaions it is generally true that aqueous solutions of complex ions with a higher positive charge on the central metal ion will have a lower pH. Explanations typically note that the greater ...
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Why is silver acetate insoluble in water?
As seen in this video, $\ce{AgNO3}$ reacted with sodium acetate $(\ce{CH3CO2Na})$ to form silver acetate $(\ce{CH3CO2Ag})$.
Why is that $\ce{CH3CO2Na}$ is soluble but $\ce{CH3CO2Ag}$ forms precipitate?...
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Why does ethyl methanoate boil after methyl ethanoate? [closed]
Ethyl methanoate boils at 54.3C but methyl ethanoate boils at 57C.
These two organic compounds have the same molecular mass. In fact, they're just made by swapping who is the acid and who is the ...
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Why is the boiling point of fluorine lower than that of oxygen?
Fluorine boils at -188.1 °C and oxygen boils at -183 °C, but shouldn't $\ce{F2}$ boil after $\ce{O2}$?
Despite being electronegative elements, both are nonpolar molecules and posses dispersion forces ...
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Are alkynes weakly polar?
I was reading about physical properties of alkynes in my Chemistry textbook.
One of the sentence states
Alkynes are weakly polar in nature.
I didn't understand how alkynes are weakly polar, so I ...
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How do compounds consisting of polar molecules dissolve?
In the case of compounds of polar molecules dissolved in water, I know it's to do with the formation of permanent dipole force of interactions between the water molecules and the polar molecules. But ...
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How can I use the MO diagram of hydrogen fluoride to demonstrate that the molecule is polar?
I am trying to explain that HF is a polar molecule using the MO diagram. Normally I say that the F atom has a higher electronegativity than the H atom, which causes a net positive dipole moment.
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Polarity vs Acidic Strength (Alcohols and Inorganic acids) [closed]
If $\ce{HI}$ is more acidic than $\ce{HCl}$ because less polarity in $\ce{H-I}$ makes it easier to donate $\ce{H+}$ ion thus increasing its acidic strength, how does more polarity in $\ce{O-H}$ bond ...
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Electronegativity, polarity, pi bonds, and nitriles
While googling some numbers, I found that the dipole moment of acetonitrile is, according to wikipedia 3.92D. Compare this to the dipole moment of ethylamine, according to NIST of 1.220D. Now, I've ...
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Polarity of 1,2-dichloroethane [closed]
I don't understand how 1,2-dichloroethane is non-polar. Both the carbons have tetrahedral arrangements of atoms and I think there should be an overall dipole. Kindly explain why isn't there a net ...
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The effect of nonbonding electron pairs on ozone polarity
I know that ozone is a polar molecule. And our master has used the existence of nonbonding electron pairs on the central atom to justify this subject.
I want to know how much the nonbonding electron ...
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Cleaning used frying oil with salt water : what is the point of using salt?
In the process of making soap from used frying oil, I need to purify the oil.
I filtered the cooking oil but I also want to remove the polar compounds that are formed during frying : free fatty acids, ...
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Does ozone have polar bonds?
Does $\ce{O3}$ have polar or non-polar bonds? My teacher says that $\ce{O3}$ has non-polar bonds.
But chem-libre texts and many other sources state that a non-polar bond has equal distribution of ...
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Bond Polarity vs bond length's effect on reactivity of haloalkanes
My textbook says:
Carbon acquires partial positive charge whereas halogen acquires partial negative charge. Halogen becomes nucleophilic in character, which can be replaced by another nucleophile on ...
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Why is the polarity of the B-N bonds in borazine the reason for its reduced delocalisation of π electrons?
My professor mentioned that borazine is aromatic, but not as much as, say, benzene. The reason he gave for this was that the B-N bonds in borazine, being polar, inhibit resonance. He also mentioned ...
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Is there a relation between polarity of molecules and their electric susceptibility?
So it is written in our text that electric susceptibility ($χe$) (the response of say water molecules in the presence of an external electric field) is related to the molecular behaviour of various ...
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Dielectric polarization: how to identify what part of the total polarization (dipolar+electronic+ionic) I need (conceptual question, I use DFPT, VASP)
I am doing polarization calculations to get data for use in other calculations. To start with, I want to calculate the static dielectric constant. However, I'm a newbie to polarization and it is a ...
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What is the direction of the net electric dipole moment in hydronium H3O+?
Assuming electric dipole moment points towards the negative charge, what would its direction be in hydronium?
Although the bonding electron density is distorted towards the more electronegative oxygen,...
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Why is HF much more covalent than KI despite having a greater electronegativity difference? [duplicate]
Generally, the percent of ionic character in a two-element compound correlates quite well with the difference in the electronegativities of the two elements making up the compound, as can be seen in ...
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Retention Time Change in Reversed Phase Chromatography (revised)
I previously learned in books that in reversed phase chromatography, retention time changes depending on the content in mobile phase, which means as the polarity of mobile phase increases, retention ...
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Ethanol and water resistant adhesives
I need an adhesive that can bind to ABS plastic but is highly resistant to ethanol, isopropanol, and water. It's for use in an environment where it will spend a significant amount of time soaking in &...
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