Questions tagged [reaction-mechanism]
The detailed (and as complete as possible) description of plausible or observable pathways leading from reactants to products of a chemical process. This tag should be applied to questions about these processes. It may be applied to hypothetical and/or proposed mechanisms.
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Reaction kinetics exercise for hydrogen iodide synthesis
The rate constant for the reaction of hydrogen with iodine is $\pu{2.45E-4 M-1 s-1}$ at 302 °C and $\pu{0.905 M-1 s-1}$ at 508 °C.
a. calculate the activation energy and Arrhenius preexponential ...
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If a reaction is not an elementary reaction, then will it be complex reaction? [closed]
Example- zero order reaction is not elementary, then will it become complex?
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Is a benzylic anion more stable or a benzylic cation?
I was revising my notes on Organic chemistry when I suddenly realised I didn't really understand what was more stable- Ph-CH2-Cl when it is about to undergo SN1, making the benzylic carbon start to ...
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Reactivity of Alkyl Halides with E2 with same number of substituents in the end
I have a question regarding the reactivity of alkyl halide for E2. I know that the general rule is tertiary alkyl halide reacts the fastest with E2, and primary alkyl halide reacts the slowest.
I was ...
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Hoffman Bromamide Reaction [closed]
Actually I couldn't understand this reaction and it's mechanism. I don't know why but everything was going smooth but I didn't felt that confidence with this reaction.
I'm very little bit of weak in ...
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How ring expansion is possible here?
Recently I have came across this question.
I went with the 3rd option as ring expansion cannot occur due to the formed stable 3 degree carbocation. But the answer key claims 4th option. How can ...
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Ozone formation
I have read this source about formation of natural atmospheric ozone claiming that the ozone creation step requires an extra molecule:
$\ce{O + O2 + A -> O3 + A}$
in order to conserve momentum ...
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What causes ionisation in redox reactions?
I'm trying to understand what's behind the ionisation of atoms in a redox reaction. I apologise if the answer to this question is obvious. I've searched around, but, surprisingly, I haven't found a ...
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Mechanism of ring expansion of epoxide
The below transformation is from
J. Am. Chem. Soc. 1990, 112, 14, 5583–5601
What does the treatment with lithium anion of ethoxyacetylene in the presence of the lewis acid do to epoxides? How does ...
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Why doesn't the reaction between molecule "B" and diethyl oxalate yield a diester?
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Why isn't this structure the answer for the second reaction?
From my understanding, the resonant structure (B) with the full negative charge on the oxygen is the most stable ...
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Why doesn’t the reaction between 3-mercaptopropionic acid and methyl iodide yield a methyl ester? [closed]
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I don’t understand why 3‐methylthiopropionic acid (X) is the correct answer. Wouldn’t sulfur and carbon have similar electronegativities?
As the consequence, isn’t it more ...
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Can someone help with GAMESS input files for heavy atom calculations (MoS2, WS2, etc.)?
I'm doing computational research on transition metal dichalcogenides for my chemistry class and I want to calculate a transition state optimization for the reaction $\ce{MoS2 +N^- -> MoSN + S^-}$. ...
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Order of radical dimerization ability
In a question I came across recently, it was asked to arrange the following radicals in the ascending order of dimerization ability.
I have read about the triphenylmethyl radical undergoing Gomberg ...
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Find the missing chemical structures in the reaction sequence
I came across the following question, where a set of reagents are used, starting from a carbohydrate derivative.
I understand that this is some total synthesis reaction, but I cannot find which one.
...
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Selective formation of enolates
I saw the following reaction on Modern methods of Organic Synthesis by Carruthers. The reaction is about the selective alkylation of trimethylsilyl enolates, and is shown below.
However, I have some ...
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Why iron reacts with steam to give Fe3O4 not Fe2O3? [duplicate]
Why $\ce{Fe}$ with $\ce{H2O}$ gives $\ce{Fe3O4}$ not $\ce{Fe2O3}$?
Like, $\ce{Zn + H2O \rightarrow ZnO + H2}$, why $\ce{Fe}$ doesn't simply gives $\ce{Fe2O3}$ when it reacts with steam?
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Which Reaction is More Thermodynamically Favourable?
I have a gaseous mixture containing $\ce{CH4}$, $\ce{CO2}$ and $\ce{H2O}$ that is being reformed via the Steam-Methane Reforming Reaction (SMR), the Dry-Reforming of Methane (DR) or a combination of ...
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Mechanism of deprotection of enol thioether
I was reading some enolate chemistry from Carruthers textbook and came across the selective alkylation of unsymmetrical ketones. The reaction involves blocking one alpha-position of the ketone using ...
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Understanding the Composition of Sodium Zincate (Na2ZnO2) Formed from Zinc and Sodium Hydroxide Reaction
I've recently conducted an experiment where I reacted zinc with sodium hydroxide to form sodium zincate (Na2ZnO2). However, I'm having trouble comprehending why sodium zincate has the composition ...
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Explain the mechanism of the following reaction, which involves a 1,2-alkyl migration with double inversion of configuration
I came across the following reaction, whose mechanism is said to involve a 1,2-alkyl migration with a double inversion in configuration. The reagents used were nitrous acid (generated in situ) ...
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Why does Williamson's Ether Synthesis ONLY follow Sn2 Mechanism
I am a high school student learning chemistry and my knowledge of organic chemistry is very limited, so pardon me if I am asking a nonsensical question.
While practicing organic, I came across the ...
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What exactly are the stages of the reaction between an oxygen ion and a water molecule?
I found information on the website water.lsbu.ac.uk - Oxygen and water:
Between altitudes of $80-\pu{100 km}$, $\ce{O2^{\small{\bullet}+}}$ and $\ce{NO+}$ ions are the dominant cationic species. $\ce{...
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Why is sodium zincate two sodium ions and two oxygen ions but only one zinc ion? [closed]
$2$NaOH + Zn ---> Na2ZnO2+H2
I have always been fascinated by this reaction because it never made sense to me why sodium zincate has such a strange composition. Why does it have two sodium and ...
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Reactivity in my standard solution of Cu, P, Al, Ca, Fe, K, Mg, Mn, Na and S in 7,8% HNO3 and H2O2
I have a problem with my standard for ICP-OES. It contains the following elements Cu, P, Al, Ca, Fe, K, Mg, Mn, Na and S in a solution of 7,8% HNO3 and H2O2.
I cannot make it work for reading P and ...
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Can Acyl halides react with PCl5, if not, why?
I was searching for reaction of $\ce{PCl5}$ with carboxylic acids and found this mechanism:
Here a corresponding acyl chloride is formed from a carboxylic acid.
Now I doubt if this is the final ...
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What mechanism do reaction of PCl5 follows, SNi or SN2?
I was taught that $\ce{PCl5}$ reacts with alcohols by $S_Ni$ mechanism as shown below:
Here it can be seen that $\ce{PCl5}$ exists as $\ce{[PCl4]+[PCl6]-}$ and so lone pair of the alcohol is donated ...
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Clarifications on enthalpy and change in heat energy
From my understanding, an exothermic reaction has a negative change in enthalpy meaning that energy is released to the surroundings. However, is it correct to say that during this exothermic process, ...
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What will be the product if ethane reacts with SO2?
At first I thought it was Reed's reaction but then I looked up the reaction and the reactant was actually $\ce{SO2Cl2}$ (sulfuryl chloride).
I couldn't find the product which would be produced when ...
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Is the "heat or UV" necessary for PVC10 + Cl => CPVC10 catalytic or endothermic and if endothermic how much energy?
Production of Chlorinated PolyVinyl Chloride (CPVC) from PVC and chlorine requires incorporating about one part chlorine in 10 PCV to achieve around 63% chlorine mass CPVC. This reaction is "...
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Why 2-methyl-1-propene's halohydrin formation does not involve steric effect?
This concerns Marc Loudon's Organic Chemistry 6th Edition's 5.2 page 187.
Consider 2-methyl-1-propene and its halohydrin formation mechanism. Usually, there will be formation of bromonium, where I ...
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Does this reaction that make an Alum happen?
One day I asked a question in high school.
The problem is “Show the reaction that occurs when potassium permanganate is added to dilute sulfuric ferrous sulfateⅡ.
The answer is $\ce{2KMnO4 + 8H2SO4 + ...
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Are these reactions in synthesis of melamine correct?
I found the Wikipedia article for melamine to be incorrect in "synthesis and reaction" section; so I decided to edit it. But on the other hand I'm not sure my assumption to be correct that ...
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Rate of SN1 reaction in derivative of furan and thiopene
When I was practising questions on the rate of SN1 mechanisms, I stumbled across this:
I could eliminate options B and D because they can stabilize by only cross conjugation (if I am correct) and ...
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What is the free radical mechanism of Ruff's degradation?
There are very few resources on the mechanism of Ruff's degradation of carbohydrates, which adds $\ce{Br2}$ to oxidize aldehydic group of reducing sugars like glucose to carboxylic acid and then adds ...
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Why does carbanion rearrangement not take place in aldol condensations?
I tried to find Aldol products for two molecules of propanal.
While doing the mechanism, I observed the formation of a $2$° carbanion, so I did a $1,2$-hydride shift to convert that into a 1° ...
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Concentration units for kinetic mechanism of combustion
I am reading Tamás Turányi & Alison S. Tomlin's Analysis of Kinetic Reaction Mechanisms (2015). On page 10-11, the authors state that for a mechanism with $N_R$ reactions involving $N_S$ species, ...
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Consequences of Nitrate fertilisers
Consider the following multiple choice.
What is the environmental consequences of the uncontrolled use of nitrate fertilisers?
The choices are.
A. Acid rain
B. Low oxygen levels in streams
C. Ozone ...
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Synthesis of Cyclohexenon from Anisole [duplicate]
(I'll write organic compounds as SMILES notation)
I am learning about carbonyl compounds these days, and I have a problem.
One way of cyclohex-2-ene-1-one synthesis is using anisole following the ...
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Pyrazole iodination
I'm now working on synthesizing 4-Iodo-1,3-dimethyl-1H-pyrazole starting from 1,3-Dimethylpyrazole, iodine, and hydrogen peroxide. I think the mechanism is just a simple aromatic nucleophilic ...
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What is the reaction between crystal violet and bleach (sodium hypochlorite) and what is the mechanism of its action against crystal violet?
I'm trying to find the reaction between bleach (sodium hypochlorite) and crystal violet, and need to find the mechanism of its action, as during my lab investigation the bleach did cause the crystal ...
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Mechanism of elimination of trans-dibromocyclooctane
I recently did this reaction according to a protocol:
And although the product formation was monitored via NMR and IR techniques, I am unable to comprehend how the product 3 was formed. It should be ...
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What does it mean Keq=1?
I’m struggling with a chemistry question related to equilibrium in a reaction. I don’t understand the meaning of $K_\text{eq} = 1$. After some research I found that when $K_\text{eq}$ is 1 it means ...
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Is a Sodium Chlorite Product Safe for Car Odor-Removal? [closed]
I would like to ask the science community's opinion about the safety of sodium chlorite for use as an odor-eliminator in an automobile's interior.
While the ingredient in the product is sodium ...
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Why sulfuric acid is used in esterification of alcohol and carboxylic acid anhydride?
I have a question regarding why sulfuric acid is used in esterification of alcohol and carboxylic acid anhydride.
I know that in case of esterification of alcohol and carboxylic acid, sulfuric acid ...
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Effects of Hydrogen Peroxide Concentration in the Briggs-Rauscher Reaction and Workarounds for Dilution
I am an IB chemistry student attempting the Briggs-Rauscher reaction, which requires a diluted solution of hydrogen peroxide. The experiment guidelines suggest diluting 400 mL of 30% hydrogen peroxide ...
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Effect of carbon dioxide impurities on the Haber–Bosch process
The Haber–Bosch process is a highly exothermic reaction that is used to produce ammonia from nitrogen and hydrogen. The nitrogen is typically obtained from the air using a membrane separation process, ...
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Free-radical addition of bromine to alkene
If light and radical initiators are present, radical addition of $\ce{HBr}$ to alkenes takes place and outcompetes electrophilic addition of $\ce{HBr}$ to alkenes. Why isn't a similar thing same ...
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Regarding the standard reduction potential and electrolyte/solid interface
I am modelling lithium-sulfur batteries ($\ce{LiS}$ batteries) and a strange phenomenom happens during charge, named infinite charging, which I show below:
The factor $f_\mathrm{C}$ that appears in ...
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Why can't ethoxide ion act as nucleophile?
Consider the reaction of chlorocyclohexane with ethoxide in a suitable inert solvent. The major product according to my textbook is cyclohexene, which implies E2 reaction pathway. Why not SN2?
$\ce{...
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How to determine the surface reaction rate and equilibrium constant for a reaction between a solid site species and gas species
Consider the following reaction mechanism 1:
S1: $\ce{C-H (s) + H (g) <=> C^\star (s) + H2 (g)}$
S2: $\ce{C^\star (s) + H (g) => C-H (s)}$
S3: $\ce{C^\star (s) + C2H2 (g) => C-H (s) + H(g) ...
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