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Are groups other than carbonyl reduced by Clemmensen reduction?
According to my textbook, Clemmensen reduction reduces only aldehydes and ketones to alkanes. But in this question:
$\ce{Zn-Hg/HCl}$ has reduced both the ketonic and nitro group. Correct answer given is D.
So, what exactly is this reduction's…
Akash Goel
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Why can't pure water conduct electricity since it can be reduced at cathode and oxidised at anode?
We all know that pure water can't conduct electricity. But during electrolysis, if add a small amount of $\ce{HCl}$ acid inside, water could be decomposed to hydrogen gas and oxygen gas, as it is reduced at the cathode and oxidised at the anode. So…
Aleser
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19
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What is the difference between molar conductance and molar conductivity?
I'm learning (or at least trying to learn) about electrochemistry, but a major obstacle to that, is that different books I refer use different terms for the same symbols. So in a last ditch attempt to clear stuff up, I've resorted to Chem.SE.
So…
paracetamol
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19
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5 answers
Un-denaturing industrial alcohol
I have a question regarding the denaturation of industrial ethanol with methanol to discourage its consumption.
The boiling point of methanol is 64.7 °C, while the boiling point of ethanol is 78.37 °C. Wouldn't it be trivial then, to separate the…
René
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19
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Why do raisins bob up and down in carbonated water?
Yesterday I preformed a fun little experiment where I poured a glass of seltzer water into a glass, then dropped a few raisins into it.
I observed that the raisins would float at the top of the glass for a few seconds, then sink all the way to the…
Scrump
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19
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3 answers
Choice of doping elements in semiconductors
In a typical semiconducting material, we start with silicon (group IV) and introduce atoms of group V or group III depending on whether we are constructing an n- or p-type semiconductor respectively.
Why is it optimal to choose doping atoms one…
SimonS
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19
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3 answers
Do modern dispersion-corrected DFT methods give more accurate molecular geometries?
I was discussing with a colleague the use of modern dispersion-corrected density functionals. I take it almost as a given that the methods generally produce "better" (for some definition) geometries, in addition to more accurate predictions of…
Geoff Hutchison
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19
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1 answer
Multiplet shape in proton NMR of morpholines
I recently carried out a Buchwald–Hartwig reaction to attach a morpholin-4-yl group to an aromatic ring:
In the proton NMR of the (columned) product, I found the peaks corresponding to the morpholine protons. The multiplet at 3.86 ppm comes from…
orthocresol
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How do I calculate the isoelectric point of amino acids, each of which has more than two values of pKa?
For most amino acids, the $\mathrm{pI}$ is simply the arithmetic mean of the amino and carboxyl $\mathrm pK_\mathrm a$s. However, for tyrosine and cysteine, which have more than one $\mathrm pK_\mathrm a$ value, this rule of thumb doesn't apply.
I…
Andrew Wolf
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4 answers
Why are there multiple lines in the hydrogen line spectrum?
Hydrogen has only one electron, yet it exhibits multiple lines in a spectral series, why is this?
Gerard
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1 answer
Why are the halogens good disinfectants?
I've been searching around the internet for a while and I know that Chlorine, Bromine and Iodine are used as disinfectants.
My question is, what is the property of the halogens that make them suitable for killing microbes? Is it just their toxicity?
Kian
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2 answers
Mechanism of a dephenylation reaction
I recently came across this reaction in my undergraduate labs. The experiment is taken from this article: J. Chem. Educ., 2008, 85, 413.
The condensation of 2-methoxynaphthalene with cinnamoyl chloride leads to the formation of…
orthocresol
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19
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1 answer
How to treat pressure in computational chemistry?
I have a reaction where a gas at high pressure and a solution with all kinds of species is involved. How do I take pressure correctly into account to get reasonable values for $G$?
Do I calculate thermochemical corrections at the given temperature…
snurden
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2 answers
Why is WF6 stable whereas CrF6 is unknown?
$\ce{F-}$ is a hard base since it is small and relatively polarizable.
Both $\ce{Cr^6+}$ and $\ce{W^6+}$ are hard acids, but shouldn't $\ce{CrF6}$ be favored since it would be a smaller hard acid?
David Jones
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19
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2 answers
Reduction of glucose to hexane with hydroiodic acid
My book (NCERT India) states that n-hexane is formed when glucose is heated in the presence of hydrogen iodide. That is, the following reaction takes place:
$$\ce{C6H12O6 + HI ->[{\Delta}] C6H14}$$
This seems a bit strange to me because I only know…
Apoorv
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