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Questions tagged [catalysis]

This tag is appropriate for reactions, their mechanisms, their kinetics, when catalysts of any kind are involved.

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How to get article access? [closed]

I don’t know if this is a suitable place for that, but does anyone have access to this article? https://pubs.acs.org/doi/10.1021/ja981969e I need it but my institution is not on the list. How could I ...
user142469's user avatar
-1 votes
1 answer
63 views

Is the acceleration of the low-temperature allotropic conversion of β-form white tin by the presence of α-form grey tin really considered catalysis?

discussion of the allotropes of sulfur in Melting point of sulfur and comments below reminded me of Napoleon's buttons, cf. Tin pest; Allotropic transformation. That section in its entirety reads: At ...
uhoh's user avatar
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How does platinum catalyses the synthesis of hydrogen and oxygen into hydrogen peroxide?

In the reaction $\ce{H2 + O2 -> H2O2}$, can platinum act as a catalyst? My teacher mentioned that and I'm wondering how exactly it works. Like what are the intermediate steps of the new reaction, ...
user145689's user avatar
0 votes
1 answer
42 views

Non-catalysed exhaust gas

I'm writing up an academic paper (medical) on in-car exhaust levels and their effect on health. So as to ensure detection of leak-points that are located further along than the catalytic converter, in ...
Medical_researcher's user avatar
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28 views

Does pH affect the activation energy of decomposition of hydrogen peroxide using iron (III) nitrate solution?

I know that pH can affect the activation energy of the decomposition of hydrogen peroxide when catalase is used, as catalase is an enzyme. However, if I use some nonenzymatic catalysts like iron (III) ...
unmyelinated neuron's user avatar
-4 votes
2 answers
121 views

The Role of Acidified Potassium Manganate(VII) in Oxidation of Alcohols [closed]

The chemical equation for the oxidation of ethanol is given as: $$\ce{C2H5OH + 2[O] -> CH3COOH + H2O}.$$ Acidified potassium manganate (VII) solution $\ce{KMnO4}$ is added as the oxidising agent. ...
ZhangJin's user avatar
2 votes
0 answers
80 views

Reduction of benzylic alcohol and halide using H2 and Pd

I am studying drug synthesis, and I found some examples that uses $\ce{H_2}$ and Pd/C or Pd/$\ce{BaSO_4}$ as catalytic hydrogenation reagents for reduction of alcohol or halide in benzylic position. ...
Krang Lee's user avatar
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How does a transition metal(eg Zn,Pd,Pt etc) break the hydrogen bond in catalytic reduction

I want to know what exactly happens with the hydrogen molecules and transition metals in catalytic reduction leading to breaking of hydrogen bonds and forming two hydrogen atoms
Arush Desai's user avatar
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0 answers
17 views

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 "...
James Bowery's user avatar
2 votes
1 answer
73 views

What is the difference between using an oven or an IR lamp to dry the coatings of fuel cells?

I wondered how the morphology of the catalyst coating for fuel cells changes if it is dried either in a conventional oven (40 °C, 60°C, 80°C) or under an IR lamp. I am pretty certain that it changes, ...
P M's user avatar
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3 votes
1 answer
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How to determine uncompensated or solution resistance of a 3 electrode setup for IR correction?

To correct for ohmic losses from the potential drop across the electrolyte due to the distance between the electrodes, electrochemical impedance spectroscopy (EIS) is typically employed to measure ...
Daniel Leo's user avatar
0 votes
3 answers
106 views

Does someone know a unique testable questions surrounding 1 of the 5 variables that affect the rate of a chemical reaction? [closed]

I am a year 11 student studying high school chemistry and we are currently studying catalysts. I am working on an assessment and need to come up with a unique but testable hypothesis surrounding one ...
Dan's user avatar
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-2 votes
1 answer
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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 ...
Harjot Dhillon's user avatar
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121 views

Ways and ideas to study ym rough surfaces with scanning tunneling microscopy

We want to study porous carbon (with nanoparticles, e.g., FeO, Ni, Au, La, Ir, Ag ...) via STM. But we run into the problem that the surface is very rough. As seen in Figure 1. Thus there is an ...
P M's user avatar
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2 votes
1 answer
104 views

Is the line between physisorption and chemisorption species specific?

I was studying about heterogenous catalysis, and my Professor said something along the line, "When the adsorption energy is comparable to (or lower than) heat of evaporation, then it is ...
Tensor's user avatar
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1 answer
60 views

Substitution of aryl bromide in synthesis of a chelator

Hello I am currently working on a synthesis of a chelator for the synthesis of a photosensitizer for photodynamic therapy. My instructor wants me to do following synthesis procedure: My problem is, ...
Mäßige's user avatar
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Hydrolysis of polyamides using solid acid catalyst

The neutral hydrolysis of polyamides (eg. nylon 6,6) does not go to completion as the reaction is reversible. You can get around this by carrying out the reaction in an acidic/basic medium. With acid ...
Adam's user avatar
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1 vote
1 answer
82 views

Effectivness factor for a cylinder

I would like to demonstrate the effectiveness factor of a porous cylinder, for diffusion-reaction (only radial diffusion, 1st order reaction, isothermal, diffusion coeff. is constant, steady-state), ...
Oquai's user avatar
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1 vote
2 answers
133 views

Determining volume of hydrogen gas evolved in water splitting reaction

I want to carry out a photocatalytic water spliting reaction. This reaction will generate Hydrogen and Oxygen gas in 2:1 ratio according to the following reaction - 2H2O + energy (light) → 2H2 + O2 So,...
Abdullah Shahriar's user avatar
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0 answers
30 views

Estimate scaled up rate of gas phase reaction

I have measured the conversion rate of a particulate-catalyzed gas phase reaction in a reactor. That is, I have a graph of how fast $\pu{1 mol}$ of catalyst converts $\pu{1 mol}$ of reactant into $\pu{...
jackisquizzical's user avatar
2 votes
1 answer
256 views

Effect of catalytic NaOH on atom economy

I conducted a base catalyzed aldol condensation using NaOH. Now I'm supposed to calculate the atom economy, AE: $$\text{AE} = \frac{{\text{MW of desired product}}} {\sum{\text{MW of reactants}}} \...
Triphen's user avatar
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1 vote
0 answers
86 views

Do PEM Fuel Cells suffer CO poisoning at the oxidizer side?

Reading about PEM Fuel Cells, first on Wikipedia then on some other sites, I notice they talk a lot about the problem of CO poisoning. But almost always it's explicitly referred to as a problem in ...
DrZ214's user avatar
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1 vote
1 answer
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Why is the sp3-sp3 reductive elimination between the R1 and norbornene in the Catellani Cycle ''not favorable''?

I have recently started reading a book about C-H activation and I cannot figure out why in the Catellani reaction cycle the R1-norbornene reductive elimination side reaction which can be a major issue ...
TheBorcanu's user avatar
2 votes
1 answer
102 views

Do asymmetrical HER/HOR catalysts exist?

Suppose I have an electrochemical hydrogen pump (Wikipedia), whereby I have an anode and cathode, each with supported catalyst, separated by a proton exchange membrane. When I apply an appropriate ...
holyjoly's user avatar
2 votes
0 answers
57 views

Which is a better poison to the Haber's process, $\ce{CO}$ or $\ce{H2S}$? [closed]

I am studying about catalysts and their promoters and poisons and came across two of the possible poisons for Fe used during Haber's process and wanted to compare their effect on the rates of reaction....
Solus's user avatar
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1 vote
2 answers
488 views

Why does base aspirin hydrolysis work better than acid aspirin hydrolysis? [duplicate]

Why does base aspirin hydrolysis work better than acid aspirin hydrolysis? I conducted an experiment and found that there was greater Salicylic Acid yield for the one I added base compared to the one ...
fdsaa's user avatar
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1 vote
2 answers
93 views

Titanium-free catalysts to decrease decomposition temperature of magnesium hydride

Magnesium hydride $(\ce{MgH2})$ is a metal hydride with a relatively stable structure, at least compared to other metal hydrides. Magnesium hydride splits at around 300 °C into magnesium and hydrogen. ...
user avatar
3 votes
1 answer
171 views

Conditions for Pd/C reduction of alkene

I am trying to do a $\ce{H2}$ reduction of cyclic alkene (otherwise simple hydrocarbon with 1 methyl group along with the chain about the weakly-strained cycle) using $\ce{Pd/C}$, the cycloalkene ...
Greg's user avatar
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4 votes
1 answer
143 views

Is the Glaser coupling reaction possible with metal alkyne complexes?

As the Glaser coupling reaction is usually done with terminal alkynes with the hydrogen being straight, I wonder if the same reaction can occur in terminal alkynes connected to the backbone of a metal ...
Evamentality's user avatar
1 vote
0 answers
37 views

What is the inherent mechanism in carbocatalysis?

When checking non-metallic catalysis materials, one mentioned example is that of carbocatalysis; using heterogeneous carbon structure to catalyze a reaction (Not to be confused as a support surface ...
Evamentality's user avatar
3 votes
1 answer
62 views

Are there any examples of chemiluminescent reaction catalyzed by Group 1/2 metals?

While researching chemiluminescent reaction that normally require enzymes but are replaced with metallic catalysts, as mentioned in this research paper: Direct and Indirect Chemiluminescence: ...
Evamentality's user avatar
2 votes
3 answers
293 views

Under what conditions does manganese dioxide lose its catalytic property?

We know that under standard conditions (room temperature and 760 mmHg air pressure) we have this reaction: $$\ce{2H2O2(l) ->[MnO2] 2H2O(l) + O2(g)}$$ Here, manganese dioxide is behaving as a ...
user avatar
-1 votes
1 answer
232 views

Rate equation for the decomposition of hydrogen peroxide with iron(III) chloride as catalyst [duplicate]

I am trying to determine the activation energy of the decomposition of hydrogen peroxide with iron(III) chloride added as a catalyst. To do that, I need to find the rate constant, but I am not sure ...
Melisa Civelekoglu's user avatar
0 votes
2 answers
85 views

Inhibitors reaction at home

For a school science project, my teacher asked me to find a reaction that can be slowed down with an inhibitor and film it at home/lab at school. He told not to use lemon on an apple or anything ...
Dang Khoa Chiem's user avatar
1 vote
0 answers
266 views

How to promote oxidation of copper(I) chloride to copper(II) chloride with oxygen in solution?

I recently discovered that copper(I) chloride in hydrochloric acid can react at about 80 °C with bubbled-in oxygen gas and oxidize into copper(II) chloride. I found almost no documentation on the web, ...
user118995's user avatar
3 votes
2 answers
328 views

When doing free radical substitution, is the free radical a catalyst?

Consider a simple free radical substitution's propagation step for $\ce{CH4}$ to $\ce{CH3Cl}$: $$ \begin{align} \ce{CH4 + Cl^. &-> CH3^. + HCl}\tag{R1}\\ \ce{CH3^. + Cl2 &-> CH3Cl + Cl^.}...
user avatar
0 votes
0 answers
70 views

Modified Arrhenius equation in the presence of a heterogeneous catalyst

Suppose we are doing heterogeneous catalysis, for example, between nitrogen and hydrogen to create ammonia in the presence of a solid catalyst, like rhuthenium. It's obvious that the gas molecules don'...
Polydynamical's user avatar
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0 answers
37 views

Why is the synthesis of graphene through alkyne trimerization not viable?

I have been looking for a rationale on this as massive polycyclic aromatic hydrocarbons have been synthesized this way, and with Graphene just being an indefinite expansion of aromatic rings, this has ...
C-Consciousness's user avatar
1 vote
2 answers
222 views

How can a catalyst be selective if it does not change the equilibrium constants?

\begin{align} \ce{CO(g) + 3H2(g) &->[Ni] CH4(g) + H2O(g)}\\ \ce{CO(g) + 2H2(g) &->[Cu/ZnO-Cr2O3] CH3OH(g) }\\ \ce{CO(g) + H2(g) &->[Cu] HCHO(g) } \end{align} As we see here, ...
Schwarz Kugelblitz's user avatar
4 votes
1 answer
171 views

Which amines show N−N coupling reaction?

We add 1 equivalent of $\ce{KCN}$ followed by catalytic reduction via Lindlar's reagent $(\ce{H2}/\ce{Pt})$ to 4-chlorobenzyl chloride (1). Verify whether the product (P) obtained will undergo an N−N ...
Parth's user avatar
  • 43
3 votes
1 answer
135 views

How are Silanol groups functionalized unto mesoporous silica structures?

As described in this research paper: Immobilization of Jacobsen type catalysts on modified silica, Jairo Cubillos , Edwing Grajales, Santiago Vásquez, Consuelo Montes de Correa, Rev. Fac. Ing. Univ. ...
C-Consciousness's user avatar
0 votes
0 answers
35 views

Regulator oxidizing NO to NO2

I have a regulator that is somehow oxidizing NO to NO2. Using a different regulator does not cause this same issue. I was wondering what could possible be contaminating the regulator that would ...
Zachary Payne's user avatar
2 votes
0 answers
36 views

Can an alloy catalyst change during a reaction?

I am studying the reaction pathway of oxygen evolution reaction (OER) on a PtNi alloy catalyst using density functional theory (DFT). What I found is that, for different intermediates, the most stable ...
Shaun Han's user avatar
  • 121
3 votes
0 answers
95 views

Why is the Tolman electronic parameter defined the way that it is?

I'm currently writing up a report on Hydrocyanation and I've been reading up on parameters people regularly use to justify their observations in regard to the performance of certain catalyst systems ...
J.Doe's user avatar
  • 161
3 votes
0 answers
120 views

Purification of Buchwald-Hartwig amination

I am conducting a synthesis involving Buchwald-Hartwig amination. I use $\ce{Pd2(dba)3}$, $\ce{P(o-tol)3}$, and $\ce{Et3N}$ as base. In many proposed mechanisms, they often omit the precatalyst. I ...
Krang Lee's user avatar
  • 1,111
3 votes
3 answers
2k views

Decarboxylation of primary amino acids

Since primary amino acids like glycine, alanine can't be decarboxylated under oxidative conditions, what would be the best catalyst for this reaction? I was thinking about copying decarboxylases with $...
steve d.'s user avatar
  • 323
3 votes
0 answers
639 views

Advantages of p-toluenesulfonic acid over sulfuric acid in the formation of acetals

I am currently working on an undergraduate experiment to form a cyclic acetal. We were asked to use p-toluenesulfonic acid as a catalyst rather than sulfuric acid. This seems to be common practice ...
jona173's user avatar
  • 567
7 votes
0 answers
485 views

Why do poisoned catalysts (Lindlar, nickel borate) result in partial hydrogenation of alkynes?

I read that alkene is more reactive than alkyne, so in hydrogenation of alkynes, it's difficult to isolate the alkenes. But with poisoned catalysts like Lindlar's catalyst or Nickel-Boron (Ni2B), they ...
Wang's user avatar
  • 621
2 votes
0 answers
453 views

What is the rate constant k for the reaction between potassium manganate and oxalic acid?

For my school's chemistry classes, I am investigating the kinetics of the redox reaction between $\ce{K2MnO4}$ and $\ce{C2H2O4}$. I analyzed the data using a colorimeter set to $\pu{565nm}$. ...
Clau's user avatar
  • 29
-1 votes
1 answer
685 views

What is the product when cyclohexanone reacts with morpholine?

The question asked to find the final product of the reaction between cylohexanone and morpholine. I attempted the reaction which is shown below: I have understood the heat symbol. It simply ...
Dusty_Wanderer's user avatar

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