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Is cyclobutadiene antiaromatic?
Cyclobutadiene is very unstable. But, some sources claim that this instability can be attributed to other factors such as ring and angle strain rather than antiaromaticity.
According to some, cyclobutadiene is simply non-aromatic (as opposed to…
Dissenter
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How to determine number of structural isomers?
I have come across many questions where I'm asked to give the number of possible structural isomers. For example number, structural isomers of hexane is 5, while the number structural isomers of decane is 75.
How can I determine the possible number…
Freddy
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26
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How does a lone pair of a central atom affect the dipole moment?
Dipole moment is the degree of polarity, i.e. the seperation of positive and negative charges. But I am not getting the intuition why and how lone pairs affect the polarity and dipole moment. I cannot connect the separation of positive and negative…
user5764
26
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5 answers
Bonding in the phosphate ion
I'm looking for an explanation of the bonding in the phosphate (PO43−) ion:
(Image courtesy of Wikipedia)
Phosphorus (15P) - being the fifteenth element - has fifteen electrons, five valence electrons and the following electron…
Au101
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Can we fill potato chips bags with a gas other than nitrogen?
I understand that we fill potato chips bag with nitrogen to prevent oxidation. But why do we use nitrogen, instead of neon or hydrogen or something else?
My first guess is that nitrogen is lighter than neon/argon but what about hydrogen or helium?
aarbee
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Why is water a dipole?
Water ($\ce{H2O}$) is a dipole. The reason why is simply because it is not symmetrical, there are more electrons on the oxygen side than on the hydrogen side, and the electronegativity of oxygen.
But why isn't $\ce{H2O}$ symmetrical like $\ce{CO2}$?…
Friend of Kim
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Are there any general rules for choosing solvents for recrystallization?
Re-crystallization is a nice way of purifying a product, but choosing a suitable solvent, if you can't rely on the literature, seems like a lot of trial-and-error.
Are there any general rules on which kind of solvents could be used for…
Mad Scientist
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What makes C=O more stable that C(OH)₂
When there are $2$ hydroxy groups on same carbon, they tend to undergo dehydration ( of course with exceptions like chloral where $\ce H$ bonding prevails).
Why does this happen? We are breaking a sigma bond in order to get a pi bond between $\ce C$…
evil999man
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How may copper acetate ligands be manipulated to change colors?
I have a solution of copper acetate and I would like to play around with the ligands to get different colors.
Background: The copper acetate was made through mixing vinegar (5% acetic acid), $\ce{NaCl}$, and $\ce{C}_{\textrm{(s)}}$. The deep…
Dale
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25
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How does the cyclopropyl group influence conjugation and aromaticity?
While answering the question Why isn't cyclobutane planar?, I recollected that cyclopropane and its derivatives behave like double-bond compounds, e.g. a cyclopropyl group can potentially be conjugated with neighboring $\ce{C=C}$ bonds and affect…
andselisk
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What is the mathematical basis behind the Jahn-Teller effect?
Both first-order and second-order Jahn-Teller distortions play a very important role in chemistry.
It is often said that the Jahn-Teller effect is based on symmetry arguments, and hence nothing can be said about the extent or the exact form of the…
orthocresol
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3 answers
Are stronger bonds always shorter?
This question relates to a few earlier questions I have seen on the site (particularly this one about the bond strength of heavier isotopes). Does a bond necessarily have to be shorter to be stronger?
To my understanding, length and strength are…
Tyberius
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Does IUPAC nomenclature have the ability to name all organic compounds?
We all know about IUPAC nomenclature. There are rules to name straight chain compounds, cyclic ones, polycyclic ones, ones with functional groups, and so on. But I have come across several examples of compounds which I simply cannot name, most of…
Pritt says Reinstate Monica
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Cyclobutadiene - Jahn–Teller effect or not?
In transition metal chemistry the Jahn–Teller effect arises when the configuration of the metal ion and d orbital splitting set up a doubly degenerate state, which is less stable than a state without the degeneracy but with lower symmetry.
In Ian…
EJC
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Is it possible to melt diamonds into a liquid?
Is it possible to melt diamonds into a liquid? I mean if you heat diamond at open air it will start to burn around 700 degrees Celsius, reacting with oxygen to produce carbon dioxide gas. In the absence of oxygen it will transform into graphite, a…
user30561
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