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Atropisomerism of naphthyl alcohol
In March's Advanced Organic Chemistry (6th ed.), it's stated that the above two are atropisomers. I don't get why is it so. How is the topmost $\ce{C}$ locked in its place? Surely, there's steric hindrance due to presence of two methyls but how…
user58382
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Why are copper salts less soluble than zinc salts?
Compounds with cations having pseudo-inert gas electron configurations have more covalent character than those that don't, therefore they should be less soluble.
Here are some solubility products:
$$
\begin{array}{lcc}
\hline
\text{Anions} &…
Aditya Shrivastava
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Where does magnetic inequivalence come from?
As the question says, I'm having trouble understanding where does magnetic inequivalence in $\ce{^1H}$ NMR come from. All the sources I've found say that two protons are magnetically equivalent if all $J$ values to all other spins in the molecule…
ralk912
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Difference between Sildenafil and Sildenafil citrate
The data I found seems to show no difference between Sildenafil and Sildenafil citrate. But if they are the same things, why Pfizer use Sildenafil citrate instead of Sildenafil as their product Viagra?
ChemicalFool
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I'm pretty sure this doesn't follow Le Chatelier's Principle
The likelihood is that I'm misunderstanding what's going on here.
Consider the reaction $\ce{A <=> B}$, where $K_\mathrm{c}=1$.
Initially, the system at equilibrium, where $[\ce A]=\pu{1M}$ and $[\ce B]=\pu{1M}$.
The system is then disturbed to…
Rational Function
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Ellingham Diagram
My textbook says the following about the Ellingham diagram:
Each plot is a straight line except when some change in phase ($\ce{s -> liq}$ or $\ce{liq -> g}$) takes place. The temperature at which such change occurs is indicated by an increase in…
user162915
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Why is enol content higher in non-polar solvents?
Apparently, for keto-enol tautomerism, the enol content of a given carbonyl compound increases when in a non-polar solvent.
What is the reason for this?
Pranjal Mittal
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Why is an energy cost associated with splitting the HOMO spins in singlet oxygen?
The molecular orbital schemes for both forms of singlet oxygen ($\mathrm{^1\Delta_g}$ and $\mathrm{^1\Sigma_g^+}$) and triplet oxygen ($\mathrm{^3\Sigma_g^-}$) are typically given as shown in the image below.
Figure 1: Molecular orbital schemes of…
Jan
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Why does like dissolve like?
Polar solvents love polar solutes to be dissolved in it and non polar with non polar. Often said as like dissolves like.
Okay, polar loving polar can be understood with help of the facts: same polar nature, same kind of interactions etc.
But how…
Pranjal Rana
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Are there molecules that take the shape of every platonic solid?
Methane is the simplest molecule I know of that takes the shape of a platonic solid — in this case, the tetrahedron. Wikipedia has a page on platonic hydrocarbons that includes molecules with tetrahedron, cube, and dodecahedron shapes. There are…
Sean Lake
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Mechanism of a gold catalyzed addition to triple bond
I needed to draw the reaction mechanism for this reaction:
So, after consulting some literature I drew this mechanism:
But, I am not sure about the last step. Does the $\ce{H+}$ just substitute the $\ce{Au+}$ ion? If so, is my last step…
Mockingbird
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Synthesis Golf V: Denopamine
A full FAQ post has been written on meta.chem.SE, explaining the premise of synthesis golf and the 'rules'. Please take a look at this before answering (if you haven't already).
This fifth round of golf concerns the synthesis of…
NotEvans.
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What is a stereochemically active or inactive s orbital?
In Concise Inorganic Chemistry by JD Lee (4th edition; adapted by Sudarshan Guha), page 73 under the section 3.6 (VSEPR Theory chapter Chemical Bonding):
...according to this theory, the position of the lone pair in $\ce{XeF6}$ molecule should be…
jyoti proy
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Etymology of alanine
Oxford dictionary online gives etymology of alanine as:
Coined in German as Alanin, from aldehyde + -an (for ease of pronunciation) + -ine.
But I see no resemblance to the aldehyde structure in alanine. Is this etymology incorrect, or am I…
user25327
16
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Why isn't cyclobutane planar?
In short, cyclobutane adopts a certain, non-planar, configuration in order to reduce ring strain caused by the fact that carbons are $\mathrm{sp^3}$ hybridised. That much is understandable.
In an exercise it was suggested to propose another kind of…
Αντώνιος Κελεσίδης
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