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When cyanide ions act as nucleophiles in substitution reactions, why is KCN the reagent of choice? Would some other source of cyanide such as NaCN or HCN work equally well in the reaction, since they should dissociate to give cyanide ions as well? |
Can NaCN or HCN be used as sources of cyanide ion in substitutions? |
> Which of the following are identical?
> [![2,3‐dihydroxy‐4‐methoxy‐4‐oxobutanoic acid isomers][1]][1]
> 1. **A** and **B** are identical
> 2. **A** and **B** are diastereomers
> 3. **A** and **C** are enantiomers
> 4. **A** and **B** are enantiomers
What I know is that when we rotate a Fisher projection b... |
Which of the following isomers of 2,3‐dihydroxy‐4‐methoxy‐4‐oxobutanoic acid are identical? |
I'm trying to find the mechanism for this reaction:
[![reaction][1]][1]
My (tentative) thought for a possible mechanism is:
[![mechanism][2]][2]
But this leaves some loose ends that I haven't been able to figure out. How does the H on OH get removed? (Does it get removed at all?) Most importantly, what is t... |
What is the function of tolene in this reaction? |
I'm trying to find the mechanism for this reaction:
[![reaction][1]][1]
My (tentative) thought for a possible mechanism is:
[![mechanism][2]][2]
EDIT: New thought for mechanism:
[![newmechanism][3]][3]
But this leaves some loose ends that I haven't been able to figure out. How does the H on OH get re... |
Might be a really silly question here but here goes. Polyethylene is a polymer with a repeating unit of just 2 carbon atoms attacked to 2 hydrogens each which connect to other repeat units.
This structure is just an aliphatic hydrocarbon like butane or hexane or decane etc. My question is, at what carbon chain leng... |
What is the function of toluene in this reaction? |
How would one determine an element simply by looking at its binding energy? |
I've seen quite a few youtube videos about electrolysis for rust removal. The process seems to be effective. My question is: how does it work?
I get that the water is ionised so we have O- and OH+ ions. I get that O2 is liberated at the anode. But what is going on at the cathode to release the rust? Is the rust chem... |
I am self studying [MIT OCW chemistry 5.111 2014][1], one of the lecture questions states the following:
> Consider a neutral atom with 8 distinct electron binding energies: −14 eV, −28 eV, −94 eV, −218 eV, −293 eV, −1730 eV, −1921 eV, and −14326 eV.
> (a) Name all of the possible ground state atoms that could ha... |
Does anybody have the literature value for the activation energy of the reaction between hydrochloric acid and sodium bicarbonate? If yes, could you please cite the source for it and the value?
I searched through the internet for hours, but the closest I could find was the activation energy between sodium carbonate ... |
I've recently learned of a compound named Chlorine trifluoride a powerful fluorinating agent. The common way to store it seems to be in regular steel drums where it flash oxidizes the inside of the drum to make a metallic fluoride. This layer of metallic fluoride keeps the substance from reacting any further with the s... |
Is fluorinated steel corrosion resistant from normal oxidation? |
I'm looking for a way to separate reaction product of iodobenzene with ethyl 2-methyl-3-oxopentanoate in 1,4-dioxane (toluene is an alternative as a solvent). The catalyst being used is Pd2(dba)3 with Ph3P as a ligand and K3PO4 as a base.
I was thinking about fractional distillation under partial vacuum because ther... |
I am trying to figure out the chemical formula for the reaction between Allura Red AC and NaClO(bleach). I have never met such reactions before in my study and I was unable, or maybe looked in the wrong places, to find the chemical equation for the reaction. The closest thing I have found is an image with the reaction ... |
Why do all [structures of $\ce N_2\ce O$][1] have Nitrogen as their central atom? Can we not draw a lewis structure with Oxygen as the central atom with 2 double bonds to the two nitrogens? This will still satisfy the octets of each atom.
[1]: https://www.youtube.com/watch?v=ZlHIQhJlWNs |
While talking about gaseous state of matter we came to the topic of London Dispersion Forces while are caused by the generation of dipole in one atom which induces a dipole in another. While talking about the cause of such I stated that since Schrodinger's equation for multi-electron atoms is time dependent and hence a... |
> Nitrogen is more electronegative than hydrogen hence N will pull electrons towards itself. Hence not a good candidate to donate electrons!
Yet it makes bonds with hydrogen, as do other electronegative elements (think of hydrogen chloride and water). So polar bonds form in all kind of molecules.
> lets take the ... |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/xQbei.png
How is the redox couple as it is written for the oxidation of $\ce{MnO4-}$, as $\ce{MnO4-,H+/Mn2+,H2O}$ correct?
I agree that $\ce{MnO4}$ is being oxidized as it loses electrons (going from -1 charge to +2) but I don't see wh... |
> Nitrogen is more electronegative than hydrogen hence N will pull electrons towards itself. Hence not a good candidate to donate electrons!
Yet it makes bonds with hydrogen, as do other electronegative elements (think of hydrogen chloride and water). So polar bonds form in all kind of molecules.
> lets take the ... |
1. What's the amount of Mercury and Thallium in a typical low-temperature thermalmeter?
2. How poisonous is Thallium when bounded with Mercury? |
How dangerous is the Mercury-Thallium filled thermometer? |
The fundamental question is: which is more acidic, 2-pyrrolidone or 2-pyrrolidinethione?
[![enter image description here][1]][1]
[![enter image description here][2]][2]
[1]: https://i.stack.imgur.com/MI8J5.jpg
[2]: https://i.stack.imgur.com/ymR2w.png
If you took a 50-50 mixture of the two and added... |
I was wondering if there are specific formulae in chemistry for which it is "compulsory" or convenient to use atmosphere rather than Pascal (or even mmHg) as a unit of measurement.
Of course we can convert one into the other, but the choice of using one of the two also conditions other units, such as in the case of... |
I was wondering if there are specific formulae in chemistry for which it is "compulsory" or convenient to use atmosphere (atm) rather than Pascal (or even mmHg) as a unit of measurement.
Of course we can convert one into the other, but the choice of using one of the two also conditions other units, such as in the c... |
I was wondering if there are specific formulae in chemistry for which it is "compulsory" or convenient to use atmosphere (atm) rather than Pascal (or even mmHg) as a unit of measurement.
Of course we can convert one into the other, but the choice of using one of the two also conditions other units, such as in the c... |
You are correct that simply stating that the Schrodinger equation is time
dependent does not really answer the question.
In fact, time-dependence is not a component of the derivation of the dispersion forces. At a surface level, they just represent how much the ground state energy of a system of polarizable molecule... |
I was wondering if there are specific formulae in chemistry for which it is "compulsory" or convenient to use atmosphere (atm) rather than Pascal (or even mmHg) as a unit of measurement.
Of course we can convert one into the other, but the choice of using one of the two also conditions other units, such as in the c... |
I'm starting the very basics of hydrocarbons and I'm having a hard time at understanding when to use the common/trivial name prefixes (sec, iso, neo..etc)
One particular problem is the difference between iso- and sec-
I seem to get a grasp of when iso-- is used. But I'm having a difficult time with sec-
It's clear w... |
Does secondary pentane exist? If so, how can it be determined? |
I am trying to figure out the chemical formula for the reaction between *Allura Red AC* and $\ce{NaClO}$ (bleach). I have never met such reactions before in my study, and I was unable or maybe looked in the wrong places, to find the chemical equation for the reaction. The closest thing I have found is an image with the... |
I have a quick question about counterion exchange. I have this very practical problem at my hands that I have a Ethylsulfate (EtSO4-) counterion for a R4N+ moeity (R = 3 different substituents). Now, I need to change the counterion to something like a BF4- or a NO3-. What would be the best approach? What role does the ... |
An acid will be 50% dissociated when the solution it's in have a pH equal to the acid pKa ('afirmation 1', for later reference).
We also know that a good buffer solution have equal concentrations of an acid and it's conjugated salt.
That's why to make a good buffer we look for an acid that have a pKa close to the... |
Can I make a buffer with a weak acid without adding it's conjugated salt, when the desired pH of the solution is exactly the pKa of the weak acid? |
An acid will be 50% dissociated when the solution it's in have a pH equal to the acid pKa ('afirmation 1', for later reference).
We also know that a good buffer solution have equal concentrations of an acid and it's conjugated base.
That's why to make a good buffer we look for an acid that have a pKa close to the... |
Can I make a buffer with a weak acid without adding it's conjugated base, when the desired pH of the solution is exactly the pKa of the weak acid? |
Why is the solution of (NH4)2[Ce(NO3)6] used as an oxidizing agent? |
Above the critical temperature of a real gas, if we compress it, to whatever extent, it doesn't get liquefied (no gas liquid interface). However, it does behave like liquids , esp. in case of very high pressures (upto 300 atm) it's physical properties are almost like liquids due to decreased intermolecular distance and... |
Does the Boltzmann distribution hold for supercritical fluids? |
I have a quick question about counterion exchange. I have this very practical problem at my hands that I have a ethyl sulfate $(\ce{EtSO4-})$ counterion for a $\ce{R4N+}$ moiety ($\ce{R}$ = 3 different substituents).
I need to change the counterion to something like a $\ce{BF4-}$ or a $\ce{NO3-}$. What would be the ... |
Choose either the unit you are asked for (as in hwk or exam) or what is useful. For instance if you want to compare pressures under different circumstances then you want to use the same units. If the pressure is large you might use kPa, if small, mTorr, etc. You may seek to avoid dealing with large multipliers (ie 3 ba... |
Choose either the unit you are asked for (as in hwk or exam) or what is useful. For instance if you want to compare pressures use the same units. If the pressures are large you might use kPa, if small, mTorr, etc. You may seek to avoid dealing with large multipliers (ie 3 bar rather than $3 \times 10^5$ Pa).
Some eq... |
I got this question this my exam
>Arrange the following in increasing order of acidic strength in gaseous phase
>(i) $\ce{CH3CH2COOH}$ (ii) $\ce{CH3COOH}$
I felt that increasing order must be (i),(ii). But answer given is (ii),(i). Why will the order change in gaseous phase? |
I got this question in my exam:
>Arrange the following in increasing order of acidity strength in gaseous phase
>(i) $\ce{CH3CH2COOH}$ (ii) $\ce{CH3COOH}$
I felt that increasing order must be (i) $\gt$ (ii). But answer given is (ii) $\gt$ (i). Why will the order change in gaseous phase? |
I got this question in my exam:
>Arrange the following in increasing order of acidic strength in gaseous phase
>(i) $\ce{CH3CH2COOH}$ (ii) $\ce{CH3COOH}$
I felt that increasing order must be (i) $<$ (ii). But answer given is (ii) $<$ (i). Why will the order change in gaseous phase? |
I got this question in my exam:
>Arrange the following in increasing order of acidity strength in gaseous phase
>(i) $\ce{CH3CH2COOH}$ (ii) $\ce{CH3COOH}$
I felt that increasing order must be (i) $\gt$ (ii). But answer given is (ii) $\gt$ (i). Why will the order change in gaseous phase? |
I got this question in my exam:
>Arrange the following in increasing order of acidic strength in gaseous phase
>(i) $\ce{CH3CH2COOH}$ (ii) $\ce{CH3COOH}$
I felt that increasing order must be (i) $<$ (ii). But answer given is (ii) $<$ (i). Why will the order change in gaseous phase? |
The [ELISA test](https://en.wikipedia.org/wiki/ELISA) on HIV works by verifying the presence of [peroxidase](https://en.wikipedia.org/wiki/Horseradish_peroxidase) within samples. The verification process is done through the enzymatic reaction that said peroxidase has on [TMB](https://pubchem.ncbi.nlm.nih.gov/compound/4... |
I was wondering if there are specific formulae in chemistry for which it is "compulsory" or convenient to use atmosphere (atm) rather than Pascal (or even mmHg) as a unit of measurement.
Of course we can convert one into the other, but the choice of using one of the two also conditions other units, such as in the c... |
I'm starting the very basics of hydrocarbons and I'm having a hard time at understanding when to use the common/trivial name prefixes (*sec*-, *iso*-, *neo*-, etc.).
One particular problem is the difference between *iso* and *sec*.
I seem to get a grasp of when *iso* is used. But I'm having a difficult time with *s... |
How does the sec-pentanyl group look? |
Choose either the unit you are asked for (as in hwk or exam) or what is useful. For instance if you want to compare pressures use the same units. If the pressures are large you might use kPa, if small, mTorr, etc. You may seek to avoid dealing with large multipliers (ie 3 bar rather than $3 \times 10^5$ Pa).
Some eq... |
Lead can undergo the following reactions when cold and hard water passes over it:
$$\ce{Pb^2+ + 2Cl- -> PbCl2}$$
$$\ce{Pb^2+ + SO4- -> PbSO4}$$
All these salts are sparingly soluble in water and have a tendency to stick to lead, rendering it passive and **not allowing plumbosolvency to occur**:
$$\ce{2Pb + 2H2O +... |
The [ELISA test](https://en.wikipedia.org/wiki/ELISA) on HIV works by verifying the presence of [peroxidase](https://en.wikipedia.org/wiki/Horseradish_peroxidase) within samples. The verification process is done through the enzymatic reaction that said peroxidase has on [TMB](https://pubchem.ncbi.nlm.nih.gov/compound/4... |
Is this a plausible reaction mechanism? (Ring closure reaction after Friedel-Crafts) |
Is Hoffman elimination anti or syn elimination? |
A steel alloy is rapidly cooled to 600oC, held for 4 seconds, rapidly cooled to 450oC, held for 10 seconds and quenched to room temperature. What phases are produced.
Why is the time reset back to 0 when you cool to 450 c? Is it because I am only considering the remaining austenite
Thanks
[![the graph in que... |
How is the rate of adsorption related to the critical temperature of a gas? My textbook says more the critical temperature, better are they adsorbed. But I cannot really understand why. They threw in another confusing statement that says that easily liquefiable gases are readily adsorbed. I am thoroughly confused.
|
How is the rate of adsorption related to the critical temperature of a gas? My textbook says more the critical temperature, better are they adsorbed. But I cannot really understand why. They threw in another confusing statement that says that easily liquefiable gases are readily adsorbed. I am thoroughly confused.
E... |
> Nitrogen is more electronegative than hydrogen hence N will pull electrons towards itself. Hence not a good candidate to donate electrons!
Yet it makes bonds with hydrogen, as do other electronegative elements (think of hydrogen chloride and water). So polar bonds form in all kind of molecules.
> lets take the ... |
Your question: How could one predict from the structure of the one product that it is going to have a blue color in that situation?
This is a very broad question. OP has to go to chemistry fundamentals to learn, how one can predict the absorbance wavelength of a compound by analyzing the structure of the given comp... |
>What role does $\ce{CuSO4}$ has in the gas sampling of an $\ce{SO2/SO3}$ gas mix in a catalytic converter for sulphuric acid production?
To give you a little context: We take gas samples from the beds of the catalytic converter to determine the efficiency of the catalyst. We use "cartridges" that we make with glass... |
Would the Lewis Structure for OF+ make it so that the formal charges are as small as possible, or would it satisfy the octet rule?
---------------
Here are my thoughts thus far:
For one, we could make the formal charge on the Oxygen +2 and the formal charge on the Fluorine -1, and give them a double bond, whic... |
Would the Lewis Structure for OF+ be drawn so that the more electronegative atom has the more negative formal charge, or would it be drawn to satisfy the octet rule?
---------------
Here are my thoughts thus far:
For one, we could make the formal charge on the Oxygen +1 and the formal charge on the Fluorine 0,... |
Under what conditions can Na<sub>2</sub>O be made from NaCl?
I know NaCl doesn't oxidise under normal ambient conditions, but in the presence of what temperature and pressure ranges is this reaction possible? |
Sodium Oxide from Sodium Chloride? |
My book says water has approximately 3.35e+28 moelcules/m^3 and that only a small part of water molecules are disociated in H+ and OH- ions and that the approximate amount of ions of each sign is 6e+19 ions/m^3.
I am trying to prove the last part , so I thought I could used the ionic product of water [H+][OH-]=1e... |
Under what conditions can $\ce{Na2O}$ be made from $\ce{NaCl}?$
I know $\ce{NaCl}$ doesn't oxidise under normal ambient conditions, but in the presence of what temperature and pressure ranges is this reaction possible? |
How to obtain sodium oxide from sodium chloride? |
There are a few clues on how to solve this question:
* you are given **binding energies**. The energies in question are just enough to liberate electrons from their bound state.
* The equation you've written $$E_{nl} = -\frac{Z_\mathrm{eff}^2R_\ce{H}}{n^2}$$ describes the binding energy. The important part is tha... |
My book says water has approximately $\pu{3.35E28 molecules/m^3}$ and that only a small part of water molecules are dissociated to $\ce{H+}$ and $\ce{OH-}$ ions and that the approximate amount of ions of each sign is $\pu{6E19 ions/m^3}.$
I am trying to prove the last part. I thought I could used the ionic produc... |
>A steel alloy is rapidly cooled to $\pu{600^oC}$, held for 4 seconds, rapidly cooled to $\pu{450^oC}$, held for 10 seconds and quenched to room temperature. What phases are produced?
Why is the time reset back to 0 when you cool to $\pu{450^oC}$? Is it because I am only considering the remaining austenite?
... |
>Would the Lewis Structure for OF+ be drawn so that the more electronegative atom has the more negative formal charge, or would it be drawn to satisfy the octet rule?
Here are my thoughts thus far:
For one, we could make the formal charge on the oxygen +1 and the formal charge on the fluorine 0, and give them a... |
> Nitrogen is more electronegative than hydrogen hence N will pull electrons towards itself. Hence not a good candidate to donate electrons!
Yet it makes bonds with hydrogen, as do other electronegative elements (think of hydrogen chloride and water). So polar bonds form in all kind of molecules.
> lets take the ... |
There are a few clues on how to solve this question:
* you are given **binding energies**. The energies in question are just enough to liberate electrons from their bound state.
* The equation you've written $$E_{nl} = -\frac{Z_\mathrm{eff}^2R_\ce{H}}{n^2}$$ describes the binding energy. The important part is tha... |
Does anyone know why the H atoms bonded with Phosphorus are not ionizable?
I tried looking in High School level books, but they only describe the process, not the real reason. I would aprecciate if someone has the answer. |
>A steel alloy is rapidly cooled to $\pu{600^oC}$, held for $\pu{4 sec}$, rapidly cooled to $\pu{450^oC}$, held for $\pu{10 sec}$ and quenched to room temperature. What phases are produced?
Why is the time reset back to $0$ when you cool to $\pu{450^oC}$? Is it because I am only considering the remaining austenite?... |
I am currently working on a project to build a filter that aims to separate or salt out the 'dirt' in shower or laundry greywater. The ideal result from this chemical reaction will be such that the *'dirt'* will be in a solid-state (precipitate). Meanwhile, the residual water will be *'clean'*. The degree of cleanlines... |
I was recently doing this organic chemistry question that tested on the concept of the formation of the intimate ion pair in the nucleophilic substitution reaction at an $\ce {sp^3}$ carbon:
$\ce {RX -> R^+||X^- -> R^+ + X-}$
This mechanism is responsible for the slight retention of configuration during an $\ce ... |
Ammonium carbonate will probably lose a proton and one of the carbonyls may be protonated. But from here onwards I can't find any leads. Does the lone pair of other oxygen atom plays a role??
Usually the heat provided may lead to a cyclic structu... |
I was recently doing this organic chemistry question that tested on the concept of the formation of the intimate ion pair in the nucleophilic substitution reaction at an $\ce {sp^3}$ carbon:
$\ce {RX -> R^+||X^- -> R^+ + X-}$
This mechanism is responsible for the slight retention of configuration during an $\ce ... |
I am working a practice problem out Ebbing Gen Chem and for part of the problem I needed to calculate delta H. The problem considers the burning of ethane in oxygen to yield carbon dioxide and water vapor. The coefficients used in the solution manual were 1 for ethane 7/2 for oxygen 2 for carbon dioxide and 3 for the w... |
One standard definition of equilibrium in beginner chemistry is that for a reversible reaction, (dynamic) equilibrium has been achieved when the rate of the forward and backward reactions are equal. We also define the equilibrium constant for a given reaction in terms of a ratio involving the concentrations of products... |
I am working a practice problem out Ebbing's *General Chemistry* and for part of the problem I needed to calculate $ΔH.$ The problem considers the burning of ethane in oxygen to yield carbon dioxide and water vapor.
The coefficients used in the solution manual were 1 for ethane 7/2 for oxygen 2 for carbon dioxide an... |
From the Wikipedia article on Skeletal formula:
"Hydrogen atoms attached to carbon are implied. An unlabeled vertex is understood to represent a carbon attached to the number of hydrogens required to satisfy the octet rule, while a vertex labeled with a formal charge and/or nonbonding electron(s) is understood to ha... |
From the Wikipedia article on Skeletal formula:
"Hydrogen atoms attached to carbon are implied. An unlabeled **vertex** is understood to represent a carbon attached to the number of hydrogens required to satisfy the octet rule, while a vertex labeled with a formal charge and/or nonbonding electron(s) is understood t... |
From the Wikipedia article on Skeletal formula:
"Hydrogen atoms attached to carbon are implied. An unlabeled **vertex** is understood to represent a carbon attached to the number of hydrogens required to satisfy the octet rule, while a vertex labeled with a formal charge and/or nonbonding electron(s) is understood t... |
> [![hexane‐2,5‐dione and (NH4)2CO3][1]][1]
> Which of the following statement is INCORRECT?
> (A) The product X has a five membered ring.
> (B) The product X is aromatic.
> (C) The degree of unsaturation of the product X is 3.
> (D) The product X has a six membered ring.
Ammonium carbonate will pro... |
From the [Wikipedia article on skeletal formula](https://en.wikipedia.org/wiki/Skeletal_formula):
> Hydrogen atoms attached to carbon are implied. An unlabeled **vertex** is understood to represent a carbon attached to the number of hydrogens required to satisfy the octet rule, while a vertex labeled with a formal c... |
Does anyone know why the hydrogen atoms bonded with phosphorus in $\ce{H3PO2}$ are not ionizable?
I tried looking in high school level books, but they only describe the process, not the real reason. I would appreciate if someone has the answer. |
There are a few clues on how to solve this question:
* you are given **binding energies**. The energies in question are just enough to liberate electrons from their bound state.
* The equation you've written $$E_{nl} = -\frac{Z_\mathrm{eff}^2R_\ce{H}}{n^2}$$ describes the binding energy. The important part is tha... |
From the [Wikipedia article on skeletal formula](https://en.wikipedia.org/wiki/Skeletal_formula):
> Hydrogen atoms attached to carbon are implied. An unlabeled **vertex** is understood to represent a carbon attached to the number of hydrogens required to satisfy the octet rule, while a vertex labeled with a formal c... |
Is this a plausible reaction mechanism? (H2SO4 cyclization after Friedel-Crafts) |
During the preparation of alkenes from alcohols, we generally heat it in the presence of Al2O3 but I don't understand the role of aluminium oxide as a dehydrating agent? How does it work as one? |
So your solution is already at a pH equal to the pKa of the weak acid you are about to add. Your hunch is that the pH remains the same after adding acid to a solution.
>[...] we will end up with what we wanted: The same concentration of the weak acid and it's conjugated base.
It depends on the concentration of wh... |
I currently did a lab where I was meant to identify factors that increase the rate of the reaction. I reacted Glucose with Potassium Permanganate and used Sulfuric Acid as a catalyst. But in my recordings I found that the more catalyst I added to my mixture, the slower the reaction took to reach its endpoint. Is there ... |
Why Does Adding Catalyst Slow Down My Reaction? |
The book I'm reading writes that for a system at constant pressure and temperature it holds:
$$dG=-TdS_{tot}$$
where $dG=dH-TdS$.
So if you want to see if a certain process is spontaneus, you just have to look at the sign of $dG$, since it depends on the sign of $dS_{tot}$.<br>
But I have a lot of doubts about thi... |
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