Questions tagged [physical-organic-chemistry]
For questions about how organic molecules and reactions are investigated using physical experiments.
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How Do Turing's Reaction-Diffusion Models in "The Chemical Basis of Morphogenesis" Relate to Organic and Physical Chemistry?
I'm reading Alan Turing's "The Chemical Basis of Morphogenesis" and its reaction-diffusion models:
https://www.dna.caltech.edu/courses/cs191/paperscs191/turing.pdf
As far as I understand ...
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Precessional frequency in H-NMR
Suppose we have a hydrogen nucleus. Now, let's apply an external magnetic field $B$. As the magnetic field is applied, the hydrogen nucleus undergoes precessional motion about its own axis with ...
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Experimental determination of ring strain energy
For my thesis I am looking to expand a part of it to include experimental means of calculating ring strain, thus far I have calorimetry covering heats of combustion and hydrogenation as well as ...
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Calculating the Barrier Between Rotamers
There are two stable conformations of a medium-sized organic molecule roughly 5 kcal/mol apart in ground state energies. One is probably the global minimum conformer identified through a conformer ...
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What is this gel byproduct of acetylsalicylic acid recrystallization?
I did a very simple acetylsalicylic acid synthesis from salicylic acid and acetic anhydride (with phosphoric acid as a catalyst). After rinsing, filtering and drying the product I dissolved it in ...
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Electrolysis of benzyl alcohol in methanol
I am conducting following electrochemical experiment on Au wires in organic medium:
I suppose the anodic reaction goes through a benzaldehyde intermediate:
The cathodic reaction is hydrogen ...
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Cation/Anion UV-Vis absorption
I want to understand how the ground state absorption of a molecule shifts if an electron is added or removed. I found these two publications 1 and 2 that observe shifts, but both times a redshift, be ...
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Energy Decomposition Analysis for SN2 involving ambident nucleophiles and an alkali metal counterion
I am wanting to perform an EDA on transition state structure of the nucleophilic attack of an ambident nucleophile (2 atoms that could be used in nucleophilic attack on the same molecule) on a benzyl ...
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How can we prevent retrogradation of starch?
Are there any additives which can prevent retrogradation of starch? I have prepared 13% of starch solution along with 2% of NaCl. The results were bit better. The synthesized gel was flowable with ...
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Band structure of solids in general
As my last question (Semiconductors and their electronic bands) was badly structured, I decided to elaborate my questions a bit.
As I now know, every solid/liquid forms a band structure, so all ...
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Why is cyclohexane more polarizable than benzene?
Looking at figure 4.2 here, we can see experimentaly that cyclohexane is more polarizable than benzene.
Why is this the case?
Intuitively, I would think that because the orbitals in benzene are more ...
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Can species with diffrent number of electrons be isoelectronic?
According to IUPAC gold book-
Does this meam that 2 species with diffrent electron number, but same valence electrons, be considered isoelectronic
Say a molecule XY and ZY where X and Z belong to the ...
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What is the probability the bonds broken with sunlight reforming back?
The maximum wavelength $\lambda$ capable of breaking a chemical bond can be estimated as $\lambda = hc/E.$
UV-A $(\pu{380 nm})$ can break bonds with the energy up to $\pu{315 kJ mol^-1},$ UV-B $(\pu{...
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Reaction Order from Percent Yield?
Referencing this paper, I am trying to approximate the order of reaction for cyclohexane (4a). Trials 1-3 provide the relevant information of mmol changes and corresponding percent yield but I'm ...
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If Qc> Kc how can forward reaction can take place
If Qc>Kc then there will be a net backward reaction but still forward reaction will take place. My problem is if Qc>Kc forward reaction will become non spontaneous right. So how can that happen, ...
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Is there a quantitative definition of inductive effect?
Usually, Inductive effects are compared using the electronegativities and distances. However, this only works in compounds with similar structures. For example, we can predict the following orders of ...
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Boiling points of hydro- and fluoro-carbons
I am teaching organic chemistry to a high school student. While discussing Teflon, we referred to the corresponding section in the 10$^\text{th}$ edition of "Organic Chemistry" by Solomons ...
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Why is the dipole moment of Anisole less than that of Phenol? [closed]
According to Wikidata, anisole has a dipole moment of 1.38D and according to this page on Researchgate, phenol has a dipole moment of 1.70D.
Resonance in anisole:
Resonance in phenol:
According to my ...
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The edge case of an edge case: Vapor emissions of the descaling agent Sulfamic acid
I am wondering about the following scenario:
What happens if ready bought sulfamic acid descaling (usually 15% cont. + $\ce{H2O}$) is vaporized or at least steam develops while very briefly descaling ...
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Does a free radical localized at one atom in a compound make sense or could it be?
In most of our cases, a dot that represents a radical is always considered affiliated to an atom in a molecule, especially when we talk about a reaction mechanism.
However, Levine's Quantum Chemistry [...
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If Ethyne has the lowest C-H bond length (highest C-H bond energy) compared to Ethane and Ethene, why is it the most acidic? [duplicate]
I am not an expert in chemistry, but these are the few facts I know from Standard XII chemistry books (these facts could be wrong or incomplete or modified by now).
Facts I know -
Ethane has 'sp$^3$' ...
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Better Way for Crushing Coconut into 500 mesh Coal for Carbonization
I am planning to use coconut as a raw material for carbonization, but I need to crush it into 500 mesh coal. Currently, I am using a mortar and pestle to grind the coconut shell into a fine powder, ...
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Finding concentration of ascorbic acid
Question:
A person applied following procedure for the determination of ascorbic acid (Vitamin C) in a sample solution.
A volume of 20.00 cm3 of the ascorbic acid sample was reacted with 25.00 cm3 of ...
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Find percentage of carbon monoxide reacted using ideal gas equation
Question
A palladium or platinum catalyst was used in an automobile to convert carbon monoxide gas to carbon dioxide according to the following reaction:
$$\ce{2CO(g) + O2(g) -> 2CO2(g)}$$
A ...
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Apparent circularity of the definition of mass [closed]
I am not a chemistry student, so forgive me for the naïvety of the question. The atomic mass of an atom is defined relatively to the mass of 1/12 of the mass of an unbound neutral atom of carbon 12 in ...
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Confusion regarding what reduction/oxidation means in reactions having covalent compounds [closed]
In the formation of NaCl, Na gets oxidised because it loses an electron, while Cl gets reduced because it gains an electron.
But how does this concept work in the case of covalent compounds, ...
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How do salts affect pH? [closed]
Since pH measures the effective proton concentration, it is the concentration of a very specific type of cation. I know if salt reacts with water, it will affect pH. But my question is, how does the ...
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What will be the product of 1 eqv Benzene reacts with 1eqv H2? [closed]
how equivalent concept is applied in the above problem, Kindly help me out with the answer and proper explanation.
As, I am getting confused in mole concept and equivalent concept here.
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What happens to polymers under high pressure?
What happens when you have polymers under high pressure? My very sketchy thoughts of polymers are that they can be thought of tangles of carbon chains surrounded by hydrogen, but that some polymers ...
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Why doesn't tetrachloromethane react with aqueous sodium hydroxide under reflux?
$\ce{CCl4}$ does not react with hydroxide nucleophile whereas $\ce{CH3Cl}$ does.
I had initially thought that it was due to symmetrical geometry of $\ce{CCl4}$ and so the dipoles cancel out and the ...
