Questions tagged [reaction-control]
Questions related to the chemical and physical influences that influence the rate and probability of chemical reactions. Not to be confused with [catalysis] or [reaction-mechanism].
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Oxidize Zinc or Nickel in black nickel plating to get browns?
I have a black nickel plating solution that is comprised of the following:
Nickel (II) Sulfate (45-50% by weight)
Zinc Sulfate Heptahydrate (20-24%)
Ammonium Thiocyanate (20-23%)
Zinc Chloride (1-3%)
...
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Pure MEA vs Aqueous MEA Solution for CO2 Scrubbing
I was wondering if using pure MEA (Monoethanolamine) or a MEA solution using water would be a better solution for scrubbing $\ce{CO_2}$.
Based on this image, I would think the key reaction would be ...
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Why is there difference in reactions in alcoholic and aqueous medium while both are polar protic solvents?
We use an alcoholic medium for reactions in which we want to prevent the characteristics of the anionic species and an aqueous medium for the reactions in which we want to control the activity of the ...
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Efficiency of Gas Liquid Reactions Using Different Methods
I am looking to react MEA (monoethanolamine) with $\ce{CO_2}$. I was planning on doing this reaction by bubbling atmospheric air through water by using an air pump. I have researched that a smaller ...
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Approximate calculations of the product distribution under kinetic control
What is the product distribution when the energy difference between the transition states (∆TS = TS1 – TS2), is at 2 kcal/mol and when it is at 5 kcal/mol (assuming room temperature)?
I know that 1.4 ...
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How much can we extend the Finkelstein reaction?
Finkelstein reaction explicitly entails the conversion of an alkyl chloride or alkyl bromide to alkyl iodide by treatment with sodium iodide in acetone.
$$\ce{R−X + NaI→[acetone] R−I + NaX↓ }\\
\ce{(X$...
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What are the products of 1 mol of vitamin C (C6H8O6) and 1 mol of hydrogen peroxide (H2O2)?
Basic stoichiometry suggests that $\pu{1 mol}$ of vitamin C($\ce{C6H8O6}$) react with $\ce{1 mol}$ hydrogen peroxide ($\ce{H2O2}$) to produce one $\ce{1 mol}$ dehydroascorbic acid DHA($\ce{C6H6O6}$)?
...
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Does high pressure reverse reaction between zinc and sulfuric acid?
When zinc is added to sulfuric acid, it undergoes a chemical reaction that generates hydrogen gas and zinc sulfate. Can this reaction be reversed by applying pressure to the products converting them ...
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Drano and Bleach reaction? [closed]
I’m not sure if anyone can answer this but I might’ve messed up, or I’m just overreacting.
My bathtub has been clogged for about a month now and I used a splash of Drano to see if it would do anything,...
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What is the difference between differential yield and selectivity?
I have a hard time understanding the difference between the differential yield and overall selectivity of a reaction.
Levenspiel, Chemical Reaction Engineering writes:
For convenience in evaluating
...
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Activation Energy in silicon etching
I'm trying to understand what does activation energy means when we're talking about etching. Here's what I understand so far:
activation energy is the energy required by the system to undergo a ...
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170
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How strong (molarity) does NaOH solution need to be to saponify fats?
I have some large cast iron hob grilles of an awkward shape, and want to clean the burnt-on fat from them using NaOH solution. I have two options
Use a small amount of a strong solution, with a brush ...
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Does the equilibrium constant of an ideal liquid mixture reaction depend on pressure?
I want to calculate the equilibrium constant K[T] for a the following reaction:
$$\ce{CH3OH(l) + C4H8(l) -> C5H12O(l)}$$
It is assumed that the mixture is ideal and the reaction takes place at 14 ...
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How does Hess' Law work exactly? [closed]
So I am talking about complicated compounds and not simple reactions where you subtract heats of formation. I was trying to find the heat of reaction for an aryl substituted methyl aryl sulfide being ...
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Rates of a chemical reaction
Consider the reaction between Calcium Carbonate and Hydrochloric Acid. I understand the reaction rate can be increased by increasing the concentration of reactants. However I can't seem to understand ...
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Why does Bachmann reaction differ in batch characteristics as opposed to flow characteristics
I have studied this reaction for over a year and it makes zero sense. When synthesizing HMX from Bachmann reaction, an important intermediate is DPT. DPT is formed by reaction of nitric and hexamine ...
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Can we make chemical bonds using light, instead of breaking them?
I am trying to bridge a conceptual understanding of how light affects both breaking and forming bonds. When bonds are broken, energy is absorbed (endothermic process). Conversely, when bonds are made, ...
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Oxidation Reactions/Reactivity of Manganese Metal in Air and Water
I am planning on doing some reactions that lead to Manganese metal and a neutral solution containing $\ce{Mn^{2+}}$ as by-products, and I wanted to try some things out with the Manganese as well.
...
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What are the reaction rate constants, or coefficients, of coal combustion at high temperature?
Say I have coal that I will combust with $\ce{O2}$ at a high temperature of $\pu{1600-1800 K}$, what are the reaction rate constants, or coefficients, of the main reactions?
I have searched around ...
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How do you rewrite molarity to weight percentage or volume percentage?
Suppose I have a molar concentration $[C]$ in $mol/m^3$ in a continuous reactor, from which the differential equation is as follows:
$ \frac{\partial [C]}{\partial t} = k[A][B] + \phi C_{,in} - \phi ...
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How does the temperature of HCl affect the reaction rate of HCl & Mg reaction?
I'm Olivia. I'm experimenting with HCl and Mg. My purpose is to find the change of the reaction rate while I increase the temperature of HCi.
According to the study, when I increase the temperature of ...
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Titanium reaction with Sodium Percarbonate solution
I've been reading about a process for darkening Titanium using Sodium Percarbonate that consists of the following steps:
Prepare Sodium Percarbonate solution 1:5 with boiling water
Soak titanium ...
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Reaction between iron oxides to form magnetite
In the notes of a course it is indicated that the reaction of formation of magnetite from iron oxides can only take place if the partial pressure of oxygen is higher than 1 nanobar.
$\ce{FeO}$ + $\ce{...
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Reaction of Grignard reagents with phosphoric acid derivatives
The use of Grignard reagents that people are most familiar with is the production of tertiary alcohols by reaction with a suitable carbonyl compound, whether it be an ester, ketone, or aldehyde. As I ...
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Is this a valid interpretation of the Mean relative speed between two (Maxwell-Boltzmann) species?
In textbooks, the collision frequency $Z_{ab}$ is always given as something like:
$$Z_{ab} = n_an_b\sigma_{ab} \Bigg(\frac{8 k T}{\pi \mu}\Bigg)^{1/2}= n_an_b\sigma_{ab} \bar{C}_{rel}$$
where the ...
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Are there any pathways that can change a solution to all colors of the rainbow?
The challenge's like this. Suppose you have a beaker containing a liquid of transparent or any color. You add some drops of another liquid and the beaker turns into, say, red after some swishing. You ...
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What is meant by "analogous reactions" in the Bell-Evans Polanyi Principle?
The BEP principle says that for analogous reactions, enthalpy change and activation energy are linearly related. What is meant by analogous reactions?
Eg. For electrophilic addition of HBr to pent-1-...
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Parameters of NaHCO3 + citric acid + H2O + NaCl mixture potentially impacting functional efficacy in pest control application?
I have been searching for infomation on this application, but have some specific questions that I have not seen directly addressed in the Google/Stack Exchange posts I've come across thus far; below ...
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Formation of Aniline from Chlorobenzene
My textbook says:
When chlorobenzene is treated with aqueous ammonia at 473K under a pressure of 60 atmospheres in presence of cuprous oxide or cuprous chloride, aniline is formed.
Notice the ...
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Temperature control and side reactions in PPAA (T3P) couplings
In a lot of procedures for amide couplings (acid + amine) using PPAA, the coupling agent is added to a cooled solution of the acid, amine, and a non-nucleophilic base such as DIPEA. This is done even ...
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Succinic anhydride esterification won't go forward
I'm trying to react succinic anhydride with a decyl alcohol to produce mono-decyl succinate. Literature and Google searches suggest that the monoesterification should proceed without catalyst. However ...
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CSTR reaction cooling jacket - Transfer Functions
I have a CSTR where an irreversible exothermic liquid reaction takes place. Coolant is flowing in the jacket of the tank to regulate the temperature of the fluid in the reactor and control in this way ...
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What are some convenient examples of so-called dissolved organic matter (DOM) for lab work?
Background, I have come across a chemical reaction system, occurring in nature, that apparently involves the presence of dissolved organic matter (in a catalytic role).
My research returns, for ...
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Why use Stork enamine alkylation?
I recently learned about the Stork enamine alkylation method of adding electrophiles to the beta carboxyl position on a molecule. But I can't seem to find out why a direct synthesis is not possible (...
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Good Hess's Law experiment [closed]
I am doing an Internal Assessment for my IB chemistry class, and I want to do something on Hess's Law, and I'll be doing it simulation based, using this website. With the solutions and equipment on ...
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Real life examples of chemical reactions [closed]
For my upcoming lab report, I want to look at exactly how a simple variable, such as heat or surface area, affects a reaction. But I'm having trouble finding a reaction to test this on, as my results ...
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Chemical reaction of radicals with different multiplicity
I am studying the chemical reaction of radicals by computational chemistry software.
I just want to know what is the rules for multiplicity.
I have two radicals for which, the ground state of one is a ...
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What is the opposite of a catalyst and examples? [duplicate]
I remember a while ago I heard of something that slowed reactions and was effectively the opposite of a catalyst. What is this called? Also would appreciate examples and an explanation of their uses ...
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What does spontaneous mean in term of forward and reverse reactions?
I just learnt about Gibb's Free Energy and was thinking about an exothermic reaction with a negative change in entropy. This means that the reaction would occur at low temperatures. But that means ...
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Reaction Of Carbonic Acid With NaCl [duplicate]
I was just wondering if it was possible for anyone to specify what reaction conditions are required for the reaction between $\ce{H2CO3}$ (Carbonic Acid) and $\ce{NaCl}$ (Sodium chloride)?
Does this ...
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How can I have iron powder without a fast reaction with oxygen? [closed]
I've seen this video in which fine iron powder reacts immediately with oxygen when exposed to the air, turning into rust.
Now, will this reaction always occur with iron powder? Or is there something ...
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Formation of Acetal from Hemiacetal?
In the reaction mechanism of formation of Acetal from Hemiacetal, why doesn't H+ attack the Oxygen of OR Group instead of the OH?
Since O in OR group has +I effect from two alkyl groups, shouldn't it ...
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How to measure the speed in a catalized reaction? [closed]
What is cheaper?
Set up a constant time of reaction and measure the concentration of the products or;
Set up a constant quantity of reactants and, with an indicator, measure the time until the ...
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Why does Sodium Bicarb. Reduce Combustion Rate? [closed]
In many common solid-propellant model rocket engines, Sodium Bicarbonate, $\ce{NaHCO3}$, is used to predictably regulate/limit the rate of combustion of the fuel. My questions are as follows:
What is ...
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Decarboxylation of THCA during CO2 Extraction of Cannabis
We have a strange problem. We are performing CO2 extraction on cannabis and we are seeing considerable decarboxylation of THCA to THC.
We have high quality temperature sensors at the heat exchangers, ...
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Is the activation energy always inversely proportional to the reaction rate?
When I obtained the activation energy using the Arrhenius equation for a 10-minute glowstick (rapid, rigorous reaction), it was almost 4 times that of a 12-hour glowstick (slow, mild reaction).
...
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Are there reactions operated at high temperature at industrial level? [closed]
Temperature is an important parameter when you deal with a chemical reaction, first of all $\Delta G$ and $\Delta G^\circ$ depend on temperature, and as a consequence the spontaneity of a reaction ...
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Controlling rate of endothermic reaction
In an experiment, I have two endothermic reactions taking place simultaneously:
$$
\begin{align}
\ce{A + B &-> C + D}\tag{1}\\
\ce{E + G &-> Z + F}\tag{2}
\end{align}
$$
$\ce{C}$ and $\...
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Why does phenolphthalein form in this reaction?
This reaction (http://orgsyn.org/demo.aspx?prep=CV1P0476) gives quinizarin as the major product in about 70% yield.
However, when the same reaction is conducted with phenol insteas of p-chlorophenol, ...
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Increasing temperature in system of dynamic equilibrium
According to the article Summary of Le Chatelier's Principle on dynamicscience.com.au, for the process
$$\ce{N2(g) + 3 H2(g) <=> 2 NH3(g)}\quad ΔH = \pu{-92 kJ/mol}$$
the forward reaction is ...
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