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.
Questions tagged [electronegativity]
234 questions
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Which molecule is more acidic: CHF3 or CHBr3?
I know that fluorine is more electronegative than bromine. However, because of the size of bromine, it is more stable with a negative charge. In the case of $\ce{HF}$ vs. $\ce{HBr}$, to me, $\ce{HBr}$ is without a doubt the stronger acid. When it…
George
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What should be the oxidation state of oxygen in HOF (hypofluorous acid)?
What should be the oxidation state of oxygen in $\ce{HOF}$ (hypofluorous acid)?
Sources on the internet have confused me. Most state its oxidation state to be 0, while the others state that it is -2 (considering the oxidation state of fluorine to…
Saharsh
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Is HF the least acidic hydrogen halide?
Fluorine is the most electronegative halogen and therefore, there is larger difference in electronegativity between the atoms of $\ce{HF}$ than any other hydrogen halide, which means the positive charge on hydrogen atom is the greatest in this…
Apoorv
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Is KF the most ionic compound?
I saw somewhere (can't recall where) that KF is the most ionic compound. I expected CsF. Does the greater polarizability of Cs allow it to more easily form covalent bonds compared to K? Does this overcome the fact that K being in n = 4 should…
Brinn Belyea
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Why are there peaks in electronegativities in d-block elements?
Looking at the Pauling electronegativities in the Periodic Table (below, from ChemWiki):
Asides from the overall trend of increasing electronegativity across and up the Periodic Table (towards fluorine), there seems to be a minor peak in the first…
user15489
17
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Electronegativity Considerations in Assigning Oxidation States
I have never seen anything other than a set of rules like these when textbooks present how to assign oxidation numbers. Such as these:
However, if we keep in mind that oxidation numbers are simply imaginary numbers which suppose all bonding to be…
Dissenter
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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 explained by the fact that the elements to the…
Teoc
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Inductive effect of phenyl ring
I completely understand how phenyl group 'releases' or 'donates' electron through resonance, but how is that a phenyl group shows a weak -I effect, despite having electrons literally smeared on itself?
Abhirikshma
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Why are noble metals more electronegative then most metals?
I was researching about electronegativity when I looked up what a graph of electronegativity within the periodic table is. And, this appeared. I scanned it, matching up everything I knew about the elements up to that table. Yep, Group 1 is all light…
HyperLuminal
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Why is HCl not considered to have hydrogen bonding?
A molecule that has hydrogen bonding usually follows these two premises.
1.) There is a hydrogen atom involved
2.) Hydrogen must be bonded to a highly electronegative element which are nitrogen ($\ce{N}$), fluorine ($\ce{F}$) and oxygen…
Luis Averhoff
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Inductive effect and hyperconjugation - one elephant, different parts?
Are the inductive effect and hyperconjugation both different ways of looking at the same phenomenon - i.e. methyl groups donate negative charge for example. Inductively we can argue that carbon is of greater electronegativity than hydrogen, and so…
Dissenter
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Why a higher s character increases a carbon atom's electronegativity?
To make us understand certain phenomenon like the higher acidity of alkynes than alkanes and alkenes, our teacher told us to learn this as a general rule:
Higher s character leads to a more electronegative carbon atom.
Note: By s character I mean…
Amritansh Singhal
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How fast do electrons move around the nucleus?
Electrons, as we all know, are incredibly small. Smaller things do tend to move faster, right? So exactly how fast considering how small they are? Also, does the electonegativity difference between two atoms alter the speed of the electron?
David Johnson
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Why is carbon dioxide nonpolar?
I understand that polarity corresponds to an electronegativity difference and that the larger the electronegativity difference, the more polar the bond.
However, I have read that carbon dioxide is nonpolar. This doesn't make sense to me.
In carbonyl…
Caters
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Why are bonds ionic when the electronegativity difference between bonded atoms is greater than 1.7?
I'm learning about how to recognise whether a bond is ionic or covalent, based on the difference in electronegativity between the two bonding partners, $\Delta \chi$.
What I have now is a formula:
If $\Delta \chi = 0$, then the bond is nonpolar
If…
LeDuc
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