The step by step sequence of elementary reactions by which overall chemical change occurs.

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A metal that melts quickly?

Is there a kind of metal that melts very quickly with very low heat or temperature and at the same time becomes hard very quickly? I'm very naive in chemistry with limited knowledge. So I hope your ...
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0answers
40 views

Michael addition reaction question [closed]

Under basic conditions, a michael addition reaction can be used to convert compound A into compound B. Show mechanism and reagents used. Explain why no Robinson annelation reaction can occur. ...
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0answers
29 views

Cross Claisen Condensation question [closed]

The cross claisen condensation of ketone A with compound B creates a 1,3-dicarbonyl compound C. Draw the mechanism for the reaction. State what property of compound B makes it ideal for this type of ...
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1answer
33 views

Malonic ester synthesis question [closed]

How can the malonic ester synthesis be used to prepare carboxylic acid A from the starting material B? Show mechanism and reagents used. Carboxylic Acid A Starting Material B
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0answers
33 views

Are multiple transition states possible? Criteria to choose the correct one?

I am studying a reaction using electronic structure methods using various software packages (ORCA,GAMESS, G09) and have found two possible transition structures between product and reactant. Both have ...
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1answer
33 views

Oxime + LiAlH4 ­­­­­­­­­

I want to know the mechanism of this reaction. My intuition says $H^-$ will attack on $C$ attached to $N$ and hydrolysis afterwards would produce $-NH-OH$. But the answer says that amine will be ...
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103 views
+50

Reaction Pathways: What to do when IRC geometries are relaxed (optimized) and the energy changes significantly

The Story: Reaction pathways can be difficult things to deal with using electronic structure methods. Intrinsic reaction coordinates (IRCs) can be determined a number of ways (a discussion of these ...
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2answers
40 views

Double Displacement Reactions that produce gas [closed]

What type of double displacement reactions can form a gas. How can i determine if a double displacement reaction will form a gas?
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104 views

C + O2 is equal to C + O, how is that possible

C + O = CO2 . This is because carbon has valency of 4 while oxygen has valency of 2. When they react the valencies are criss crossed which means we will get C2O4 but this is simplified to CO2. But ...
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3answers
69 views

Aldol of 7-oxo octanal

I want to do intra molecular aldol condensation of 7-oxo octanal. I am talking about the major product. Clearly, A 6-membered ring would be a major product, but there are 2 possibilities. Taking ...
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1answer
48 views

What is CO + 2H2 on normal pressure

In the pressure of 340 atm, $\ce{CO + 2H2 <=> CH3O}H$ But what is its product during normal pressure of 1 atm. I think it would be a single displacement reaction of $\ce{CO + 2H2 <=> CH4 + ...
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3answers
377 views

CH4 + O2 => CO2 + 2H2, what's wrong with it?

It says in my textbook that $\ce{CH4 + 2 O2 -> CO2 + 2 H2O}$, this seems like a displacement reaction to me but then shouldn't it be $\ce{CH4 + O2 -> CO2 + 2 H2}$ since $\ce{4 H}$ is displaced ...
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1answer
47 views

Preference of grignard between aldehyde and double bond?

Quick question, in this reaction: 2-Butenal + CH3MgBr --> ?? Will the grignard attack the double-bond or the aldehyde carbon? Please explain this preference, thanks!
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1answer
26 views

Why can't the molecularity be determined from the rate law?

Basically can someone explain why the molecularity cannot be determined from the rate law?
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2answers
79 views

Why does free chlorine in the stratosphere lose its ozone-depleting potential after about 100,000 reactions?

Free chlorine ($\ce{Cl}$) in the stratosphere can deplete ozone ($\ce{O3}$) as follows: $$\ce{Cl + O3 -> ClO + O2}$$ The chlorine atoms can then react with oxygen and return to the beginning of ...
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2answers
42 views

What purpose do chain reactions serve?

I just learned what chain reactions are, but I can't seem to wrap my head around them because it seems utterly useless and doesn't accomplish anything. At least that's how I understood it because the ...
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161 views

Why is it necessary to avoid even traces of moisture from a Grignard reagent?

This fact was written in my text book. I wonder why that should be so.
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1answer
56 views

Is there a relation between the ionization energy and the electron affinity?

I am aware of the definition and equation of IE and EA. I was wondering if there is a direct relation between this two quantities with the energy of the neutral specie.
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1answer
107 views

Why isn't 4-hydroxybenzoic acid formed along with salicylic acid in kolbe's reaction?

I've read that in kolbe's reaction of phenol, i.e. reaction of phenol $(\ce {C6H5OH})$ with $\ce{NaOH}$ forming sodium phenoxide $(\ce {C6H5O^{-}Na^{+}})$, followed by reaction with $\ce{CO_2}$ and ...
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1answer
88 views

Rate and order confusion

I just learned about rate and order... I just want to confirm if these three ideas are correct: If the first elementary step is the slow step, will the stoichiometric coefficients of the reactants ...
2
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1answer
67 views

Diels Alder reaction with maleic anhydride. Reactivity of different dienes

I don't understand question 6, although I took notes and the professor mentioned an explanation in class. Can someone please help using easier terms?
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1answer
42 views

How do you find the average rate and instantaneous rate given a kinetics plot?

What is average rate? What is instantaneous rate? How do you find these? My teacher described finding the tangent to a graph. I am not sure what is meant by this.
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1answer
65 views

Decomposition of potassium permanganate under prolonged heating

When we heat potassium permanganate, the equation of the decomposition of it is: $$\ce{2KMnO4 ->[\Delta] K2MnO4 + MnO2 + O2}$$ So what will happen to potassium manganate ($\ce{K2MnO4}$) when ...
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2answers
71 views

Organic chemistry Reaction mechanism

Which one is more stable, alkyl carbocations or aryl carbocations and why?
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1answer
55 views

Reaction of phenol with Zinc dust

I have seen this reaction many times: $\text {Phenol}+\text{Zn}\ce {->}\text{Benzene}+\text{ZnO} $ But what is the mechanism?! Tried a lot but couldn't cook up one... Thanks for any help...
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1answer
378 views

Rate and mechanism of the reaction of Mg and HCl

In the reaction between hydrochloric acid and Magnesium the overall reaction is: $$\ce{Mg + 2HCl -> MgCl2 + H2}$$ My proposed mechanism of reaction is that $\ce{HCl}$ dissociates in $\ce{H2O}$ ...
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1answer
77 views

Reaction Order Greater than 1

What is the chemistry behind why reactions of order >1 exist? And what role does the number of activated complexes formed have in determining reaction rate?
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1answer
68 views

Rate of reaction increases exponentially with concentration

In our chemistry practical we dropped 0.07g of Magnesium into various concentrations of an acid (sulfuric or hydrochloric - only one was used, not sure which), and measured the rate of reaction by the ...
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Reasons for dry conditions in substituition reactions with benzene

All substitution reactions of benzene must be carried out in dry conditions with a catalyst that produces a powerful electrophile. This was a statement from my book. My question is, why must it ...
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2answers
104 views

Is there a general way to predict products of a chemical reaction

Is there a general way to predict products of a chemical reaction, given only the atomic masses of masses of all elements involved? for example: 1)$\ce{CuFeS2 + O2->}$ 2)$\ce{K2CrO4 + ...
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2answers
99 views

Why does gold react with cyanide and sodium hydroxide

Why does gold react with cyanide and sodium hydroxide and what is the chemical reaction's impact on gold's atomic structure and bonding? What I think is since in the 'flotation' process, when the ...
2
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1answer
621 views

Why use glacial acetic acid in bromination of anisole?

In my organic chemistry lab (next week, the experiment has not been conducted yet) we are being asked to react anisole with bromine to get 2-bromoanisole (as well as 2,4-dibromoanisole and all the ...
5
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1answer
51 views

Molecular Oxygen in Suzuki Homocoupling

I'm curious as to the role of molecular oxygen in Suzuki homocoupling reactions, as discussed here. In a standard Suzuki cross-coupling reaction, molecular oxygen is not required. However, this paper ...
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4answers
130 views

How could I create a machine that as rapidly as possible creates greenhouse gases from air?

For a very large-scale project, I am trying to create a greenhouse gas demonstration device, which rapidly produces greenhouse gases from atmospheric air using only electricity, or any chemical ...
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1answer
40 views

First Order Reaction

The half-life of the first order reaction, A → products, is 33.8 s. What was the original concentration, [A]O in mol/L, if after 2.5 minutes, the concentration of A is 0.0796 mol/L? Round your answer ...
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57 views

what are reduction oxidation reactions?

in the picture, the product is a neutral material, but in the illustration of the molecular structure, the compound is shown in its ions, why we can't show it in its ions even in the equation or if ...
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1answer
41 views

What aspects of a molecule's chemical makeup determine which portions of it will react?

Is there a specific way to know how two or more arbitrary molecules will react? An example that prompted this question: $\ce{(HOC6H4)2CMe2 + 2 NaOH → (NaOC6H4)2CMe2 + 2 H2O}$ (from here). How can ...
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1answer
69 views

Why does glass shatter when heat is applied to it?

When I poured hot tea into a cup, the cup shattered after about three seconds. The cup was made of glass. It was pretty thin. How did the glass and the tea react in terms of chemicals. This is a bit ...
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1answer
46 views

How do ligands and coordination complexes work in this case with copper (II) chloride?

What happens when Ammonia is added to an (aq) solution of copper II chloride? $\ce{CuCl2 + NH3 ->\; ?}$ I know that ligands bond with metals to form ion but I'm not sure about how they work in a ...
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1answer
27 views

Is there a name for the pair (c, R), where c is the stoichiometric coefficient of a reactant R in some chemical reaction?

I am programming a simulation, and I need a good name for a data structure that stores pairs $(c, R)$, where $c$ is the stoichiometric coefficient of a reactant $R$ in some chemical reaction. Is there ...
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1answer
58 views

What's the mechanism of the reaction of (E)-methyl 3-(furan-2-yl)acrylate in acidic methanol?

In the organic chemistry textbook by Clayden et al. they mention that the reaction of (E)-methyl 3-(furan-2-yl)acrylate in acidic methanol yields dimethyl 4-oxoheptanedioate without providing the ...
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2answers
71 views

Dry ice and acetone

In my organic chemistry class there are several reactions that I've been told are generally conducted at -78 C, which is apparently also the temperature of dry ice in acetone. This is all well and ...
7
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1answer
152 views

Electrophilic Aromatic Substitution: Are protonated OH-groups ortho-/para- or meta-directing?

In Electrophilic Aromatic Substitution ($\text{S}_{\text{E}}\text{Ar}$) reactions groups that can donate an electron pair into the aromatic ring, e.g. $\ce{-OH}$ or $\ce{-NH2}$, are ...
2
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1answer
45 views

Determining order of a reaction without isolation

I'm writing a computer program to calculate the order of a chemical reaction with respect to each reactant. When I do this by hand, it's easy to isolate which reactant concentration stays relatively ...
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1answer
245 views

Limiting Reactants without a given mass

This is a question I have for Chemistry homework, but I don't understand how to solve it without a given mass. I narrowed the choices down (see below _) I know a limiting reactant well limits the ...
2
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2answers
77 views

Reaction between Zinc and Sulfur

Would the reaction between zinc and sulfur be $$\ce{Zn_{(s)} + S_{(s)} -> ZnS_{(s)}}$$ or $$\ce{8 Zn_{(s)} + S_8\ _{(s)} -> 8ZnS_{(s)}}$$ I know that $\ce{S}$ and $\ce{S8}$ are allotropes of ...
1
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1answer
53 views

Enthalpy of Zinc and Sulfur Reaction

I was working on my homework which was to write a description of what would occur if zinc and sulfur reacted and what steps would a scientist have to make in order to make them react. When I ...
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0answers
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Symmetry element in the coversion of cyclopent-2-enyl anion to pentadienyl anion?

I'm trying to draw the state correlation diagram for the reaction of cyclopent-2-enyl anion to pentadienyl anion but I don't know which symmetry element is preserved in this reaction. What could it ...
2
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1answer
44 views

Does anyone know where I can find the reaction rate coefficient and design equation for the electrolysis of brine and sodium hydroxide solution?

equation 1) $\ce{2 Cl^{–} -> Cl_2 + 2e^{-}}$ equation 2) $\ce{2 H2O + 2 e^{–} -> H2 + 2OH^{–}}$ These equations are the key reactions in the chlor-alkali process. I want to model a reactor ...
2
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1answer
47 views

Which of the these SN1 solvolysis of two alkenyl bromides reactions is faster?

The SN1 solvolysis of one of the following alkenyl bromides is in MeOH approximately 100000 times faster than the other one. Which is the more reactive one? Draw the mechanism including the ...