Questions tagged [electronegativity]
Refers to ability for an atom in a covalent framework to attract electron density to itself. Do not conflate with electron affinity, which is the ability of a lone atom (or molecule) to attract an electron to itself. Both are measured in joules/mole.
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Why is the OO-H dissociation is unlikely for the Caro's Acid?
Let us consider the Caro's Acid: $\mathrm{H_2SO_5 \equiv SO_3H-OOH}$.
It is widely known that the hydrogen tied with the $\mathrm{-OO-}$ group is pretty much unlikely to dissociate:
$$ \text {...
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Scale to be considered for comparing electronegativities of nitrogen and chlorine
The Pauling scale gives the $\chi$ values of $\ce{N}$ and $\ce{Cl}$ to be $3.04$ and $3.16,$ respectively, but the Allen scale gives the $\chi$ values of $\ce{N}$ and $\ce{Cl}$ to be $3.066$ and $2....
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Change in inductive effect of a susbstituent when -R group replaces -H atom
There are several examples where the negative inductive effect of a substituent gets increased when a hydrogen atom on that substituent is replaced by an alkyl group.
Some particular examples:
$$\ce{...
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Why does Pb have a higher electronegativity than Sn?
I recently learnt that electronegativity generally decreases as I move down a group and from right to left within a period. However, according to the table below, Pb has an electronegativity of $2.33$,...
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Electronegativity of heavier elements of Group 15
While reading about p-block I got to know that in Group 15 elements
electronegativity value decrease down the group but amongst the heavier elements difference is not that much pronounced.
I ...
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Displacement by more electropositive metal in non aqueous environment
The more electropositive element should displace metal from it's salts' solution. This can be seen in reaction of copper salts with iron. But, if you try using for example potassium metal as the more ...
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Does H2SO or H2CO have a higher dipole moment? [closed]
Given these two molecules, I realize that the molecules are pretty identical in terms of the individual atoms' electronegativities (with Sulfur only being a small bit higher than Carbon). So then, the ...
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Determining which compound is more 'ionic'
I was going through my chemistry textbook (IB Pearson), and it explicitly stated that the higher the absolute difference between the electronegativity of elements in a binary compound, the more 'ionic'...
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Ambiguous oxidation state of phosphorus in phosphorous acid
I was doing a question in which we were required to find the oxidation state of $\ce{H3PO3}$. I knew the structure that is:
Now, phosphorus being less electronegative than oxygen gets $+2,+1,+1$ ...
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Bent's rule: electronegativity and s character
I'm very much confused about Bent's rule. What I perceive from it is that more electronegative element occupies a position which has less s character.
What I can infer from here is that s character ...
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The most acidic hydrogen of 4‐hydroxybutanenitrile
Identify the most acidic hydrogen atom in the compound below:
$$\ce{NC-CH2-CH2-CH2-OH}$$
My teacher said that the $\ce{H}$ connected to $\ce{O}$ is the most acidic since $\ce{O}$ is more ...
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Hydrogen Bonding by Carbenes
A hydrogen bond is formed between hydrogen attached to highly electronegative atoms (nitrogen, oxygen, and fluorine) which are small in size too and the non-bonding pair of electrons of another such ...
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Which substitutent should be placed on axial position in SCl2(OCH3)2?
According to Bent's rule, in $\mathrm{sp^3d}$ more electronegative element is placed on the axial position, so between $\ce{Cl}$ and $\ce{OCH3}$ in $\ce{SCl2(OCH3)2}$ which should be placed on axial ...
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Why must polar molecules be asymetrical? [duplicate]
As I understand, polarity in molecules comes from the difference in electronegativity or the ability of the atoms to attract eletrons so the electrons spend more time or are more probable to gravitate ...
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Relationship between electronegativity and atomic radius [closed]
Would someone please explain in detail the relationship between the two? I understand that atomic radius is related to ionisation energy but I can't see how atomic radius may be related to ...
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Reference for electronegativities of different metal oxidation states
A long time ago I was researching the effect of the self regulatory response in Fe and Co. I found that my results made sense based on the idea of the electronegativity of the ions considered. I found ...
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How to determine polarity of components in TLC
Estimate how a TLC-analysis would look like for the following reaction when you take a TLC at: a) the start of the reaction, b) after 65% conversion and c) after full conversion of A. (You may assume ...
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Why do Hydrogen Halides(with the exception of HF) form mostly strong acids? [duplicate]
Why do Hydrogen Halides(with the exception of HF) form mostly strong acids?
My guess is that the negatively charged Halide part of the molecule is attracted by the partially positive part of the water ...
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What is the correlation between electronegativity and the sharing of electrons?
For example in a C-O bond, the electronegativity difference is 1.2. does this mean that the Oxygen has 1.2 of the shared electrons and Carbon 0.8 (or some other numbers)? Is there a specific equation ...
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Confusions about inductive effect and acid strength
If one of the hydrogens in the alkyl side chain of ethanoic acid is replaced with an atom of Chlorine, the acid has a larger Ka value. My book says this is since the Cl "borrows" electron density from ...
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Can an element have variable oxidation states in a compound?
Take propanoic acid for example. If I assign oxidation states to the 3 carbons in it using the idea that the more electronegative element gets all the electrons in the bonds it makes, the 3 carbons ...
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Relationship between effective nuclear load and periodic properties
The effective nuclear charge is defined as the net positive charge experienced by an electron in a polyelectronic atom. It can be calculated using the well-known Stars Rule.
Once I have calculated ...
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Which Oxygen atom in HCOOH (formic/methanoic acid) does Carbon donate its electrons to, to obtain a partial positive charge?
I was wondering if the Carbon atom in HCOOH (methanoic/formic acid) forms a positive partial charge by donating its electrons to both the Oxygen atoms, since they both possess a higher ...
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Does a C=C double bond donate electron or withdraw it?
I have learned that a $\ce{C=C}$ double bond is electron-rich because of the p-p overlap and hence can easily donate an electron pair: I agree with this statement.
However, in a $\ce{C=C}$ double ...
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Why is carbon monoxide a monodentate ligand
Carbon monoxide has lone pairs on both the carbon and the oxygen atoms. However, I have never seen any complex where the oxygen atom or both the oxygen and the carbon atoms are the donors.
I know ...
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Where will a H+ attack on 6-hydroxyhexan-2-one? [closed]
Where will a H+ attack on 6-hydroxyhexan-2-one? Protonation can take place either on the ketone or the alcohol. So where will it attack? In short, on which of the two oxygen atoms is electron density ...
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Why is hydrogen not very electronegative? [closed]
I looked at my reactivity series and I have just realized that hydrogen and carbon are both included in the series, even though they are non-metals. So why is hydrogen more electropositive than ...
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Why is fluorine one of the most electronegative atoms even though it doesn't have the largest effective nuclear charge?
Why doesn't electronegativity increase as the effective nuclear charge increases? Most atoms with a higher atomic number than fluorine have a higher effective nuclear charge. However, flourine is a ...
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why fluorine and oxygen have different behaviour towards electron gain enthalapy and electronegativity? [closed]
I have seen following definitions in my textbook:
Electron gain enthalapy may be defined as enthalpy change taking place when an isolated gaseous atom of the element accepts an electron to form a ...
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Comparing Acidic Strength of H3PO4 and H3AsO4
The $\mathrm{p}K_\mathrm{a}$ values for $\ce{H3AsO4}$ and $\ce{H3PO4}$ are $2.30$ and $2.12$ which indicate that $\ce{H3PO4}$ is a stronger acid compared to $\ce{H3AsO4}$. I looked up their ...
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Effect of Electronegativity on Bond Angles in NH3 and NF3 [duplicate]
I am reading a book: Concise Inorganic Chemistry by J.D.Lee (Fifth Edition)
In the chapter-The Covalent Bond, the author says:
$\ce{NF3}$ and $\ce{NH3}$ both have structures based on a tetrahedron ...
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Why is the electronegativity of indium greater than that of thallium?
Why is the electronegativity of indium greater than that of thallium?
One possibility which I had assumed was the poor shielding effect by the d and f orbitals which leads to an increase in the ...
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Why do atoms have electron Affinity? [duplicate]
Atoms are stable so how can they pull electrons i.e how do they have any electron affinity at all?
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Will there be change in electronegativity difference in C-O and C=O?
Is there any change in EN difference in C-O and C=O. If yes, why?
Does EN difference change if its bond is changed to single, double, or triple?
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Why does C=O have a larger dipole moment than C-O?
Why does $\ce{C=O}$ have a larger dipole moment than $\ce{C-O}$?
According to me, dipole moment directly depends upon bond length and electronegativity difference. In $\ce{C=O}$ and $\ce{C-O}$, (I ...
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What measures of the dielectric constant mark whether the solution is ionic, polar and nonpolar? [closed]
At what numerical values of ε, then what organic compounds if any mark these thresholds. How is that only for a vacuum has ε=1? This is absolute lowest limit?
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Intramolecular or intermolecular?
I am extremely confused about these types of forces.
Some websites state that the forces in the covalent bonds of carbon dioxide are inter. Other websites say they are intra?
Also, some websites say ...
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How does changing substituents change the electronegativity of the carbon atom attached to it?
I was wondering how electronegativity and charge of carbon atom is affected by switching the substituents.
For example, what will be the difference in electronegativity of carbon atom in $\ce{-CF3}$, $...
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Why don't I get the same value of percentage ionic character of a particular molecule from different equations?
About the ionic character of a polar covalent compound Pauling gave two equations as
[1-$e^{.25(x_a - x_b)}] $%
[18$(x_a-x_b)^{1.4}$]%
Hanary and Smith gave the equation
[$16(x_a-x_b)+3.5(x_a-...
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What is the reaction mechanism between a basic oxide and an acid?
For instance in $$\ce{ Li2O (s) + 2HCl (aq) -> 2LiCl (aq) + H2O (l)}$$ I am wondering why the $\ce{Cl}$ displaces $\ce{Li}$ .I figure that oxygen is negatively charged as it pulls the electron from ...
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electronegativity and hydrogen bonding [duplicate]
I have a basic idea why, but can someone just confirm, why chlorine isn't able to hydrogen bond despite the fact that it has the same electronegativity value as nitrogen.
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Bond angles in NH3 and NCl3
The bond angle in a molecule is inversely proportional to the electronegativity of the surrounding atom if the central atom is same. This also happens with $\ce{NH3}$ and $\ce{NF3}$, as bond angle in $...
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Directional nature of the acetamido group in electrophilic substitution reaction
Here, in $\ce{CH3CONH2 -}$ group, the nitrogen has a lone pair and can thus activate the benzene ring along with having an ortho-para directive effect in the following manner:
However at the same ...
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Why in SN1 reaction the order of reactivity of alkyl halides increases from fluorine to iodine?
In $\mathrm{S_N1}$ mechanism alkyl halides need to be ionized, so wouldn't it make more sense if alkyl fluoride reactivity were the most, since it is the most electronegative element?
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Do some electrons transfer if I connect with a conductor 2 solid pieces of 2 different elements with different electronegativity? [closed]
Making some researches to answer my last post, I found this article.
It explains that when a piece of zinc and a piece of copper are connected with a conductor, since copper is more elctronegative ...
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Is there any mathematical formula for electron affinity and ionization potential?
I already know about the mathematical formula for electronegativity, but it requires the ionization potential and electron affinity. How can I can easily calculate the ionization potential and ...
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Why do some elements with high electronegativity exhibit metallic properties?
Metals typically have low electronegativity, which makes them form ions easily and prefer making metallic bonds to covalent. However, some of them seem to disprove that. Take, for example, gold, lead ...
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Confusion between electronegativity and electron affinity
Electronegativity is a chemical property that says how well an atom can attract electrons towards itself.
The electron affinity of an atom or molecule is defined as the amount of energy released ...
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Why is the bond dissociation energy of C-H bond higher than that of a N-H bond?
Looking at a chart of BDEs (bond dissociation energies) regarding elements bonded with hydrogen, the general trend seems to be that the BDE increases as we go to the top and to the right. This can be ...
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Is it possible to calculate electronegativity of surface atoms?
As the title asks, is it possible to calculate the electronegativity (EN) of specific atoms on extended surfaces (slabs), more specifically using computational methods? There are a few issues here I ...
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