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My problem sheet asks me: " Draw a mechanism for the formation of $EtCH_2COOH$ from the reaction of $MeCOCH(Et)COOEt$ with $NaOH$ in $EtOH$"
This has got me stumped. The mechanisms that I have attempted use the hydroxide ion as the base/nucleophile, is this right? My initial thoughts were to make the enolate by depr... |
My problem sheet asks me: " Draw a mechanism for the formation of $EtCH_2COOH$ from the reaction of $MeCOCH(Et)COOEt$ with $NaOH$ in $EtOH$"
This has got me stumped. The mechanisms that I have attempted use the hydroxide ion as the base/nucleophile, is this right? My initial thoughts were to make the enolate by depr... |
First question regarding corrosion of iron: **why is anodic area always located at nicks and scratches, where energy state is high?** (does"high [potential] energy" mean unstable structure?)
![enter image description here][1]
Second questions(refer to the image): **why and how does $Fe^{2+}$ move to the top of the iron... |
First question regarding corrosion of iron: **why is anodic area always located at nicks and scratches, where energy state is high?** (does"high [potential] energy" mean unstable structure?)
![enter image description here][1]
Second questions(refer to the image): **why and how does $Fe^{2+}$ move to the top of th... |
>If the absorbance of one of the buffer solutions (pH = 4.623) was 0.319 and the absorbance of the basic solution was 0.625, what is the $\mathrm{p}K_\mathrm{a}$ of the indicator? Include activity coefficients in the calculations.
The correct answer is 4.927, but I don’t know how to approach the problem to get the r... |
According to my organic chemistry textbook, Cis-Decalin has the two rings nearly perpendicular to one another, with the middle hydrogens cis to one another. Trans-Decalin has the ring nearly flat (planar), with the middle hydrogens trans to one another.
However, typing Cis-Decalin and Trans-Decalin into ChemBioDraw ... |
I have a **FAT** question. This may sound cliché! Because we are in the era of "trans-fat" free, "unsaturted" food. Not to mention it's the period *where people get sicker and die faster (oh may be, the statistics weren't obvious in the past...)*.
Fats are important part of our diet and major source of energy (*the... |
When disqualifying trans fat, are we qualifying cis-fat as healthy? |
Standard Gibbs free energy of formation of liquid water at 298K is -237.17 kJ/mol and that of water vapour is -228.57 kJ/mol. Therefore, $$\ce{H2O(l)->H2O(g)}~~\Delta G=8.43~kJ/mol$$
Since $\Delta G>0$, it should not be a spontaneous process but from common observation, water *does* turn into vapour from liquid over... |
Why does water evaporate spontaneously at room temperature despite dG > 0? |
>If cis is what's naturally found, by default it's unsaturated fat isn't it?
Both cis and trans are unsaturated. "Unsaturated" means having at least one bond that is not a single bond (but instead a double or triple bond). The terms [cis and trans][1] refer to the geometry of the molecule about the double bond. ... |
Standard Gibbs free energy of formation of liquid water at 298 K is −237.17 kJ/mol and that of water vapour is −228.57 kJ/mol. Therefore, $$\ce{H2O(l)->H2O(g)}~~\Delta G=8.43~\mathrm{kJ/mol}$$
Since $\Delta G>0$, it should not be a spontaneous process but from common observation, water *does* turn into vapour from l... |
>If cis is what's naturally found, by default it's unsaturated fat isn't it?
Both cis and trans are unsaturated. "Unsaturated" means having at least one C-C bond that is not a single bond (but instead a double or triple bond). The terms [cis and trans][1] refer to the geometry of the molecule about the double bon... |
Having never prepared a buffer solution before, I am hoping for a little help in understanding the process.
[This method](http://www.whitelabs.com/files/Alkaline_Methylene_Violet_Solution.pdf) I plan to use calls for a 0.1M glycine buffer at pH 10.6. Some internet searching yielded [this recipe](http://microscopy.b... |
How do I write a figure legend for a thin layer chromatography plate drawing? |
A "reaction map" in my lecture handout suggests that the product of this reaction is: ![enter image description here][1]
[1]: https://i.stack.imgur.com/TU34N.png
So, basically overall it just merges two ethylacetoacetate molecules together at the central carbon. What is the mechanism for this? My thoughts are t... |
I've been searching the web for this phenomenon and surprisingly I found only one post about it. And [the reply][1] to this [question about canned air][2] begins with words:
> I don't know about the shaking part (it is hard for me to see how that would make a difference)
This beginning has strongly shaken my fai... |
What causes spray cans to get cooler when shaken? |
I need to compare the hydrophilicity of those materials to compare contact angles of water with those materials' surfaces for surface tension measurement. Materials are:
PTFE Teflon, PVC, PS, PVDF, Si-Wafer-Si-SiOx, Parafilm and PMMA
Ordering the polarity can also work. Where can I found such a comparison? Can so... |
Today, I'm looking for how to find the 2nd perturbation to the base in Rayleigh Schrödinger Perturbation Theory (RSPT).
**SETUP**
Starting from the 2nd order perturbation:
\begin{equation}
\hat{H}^0 |n^2\rangle + \hat{V} |n^1\rangle = E_n^0 |n^2\rangle + E_n^1 |n^1\rangle + E_n^2 |n^0\rangle
\end{equa... |
I'm trying to figure out which form of chromium oxide forms naturally in our atmosphere, i.e., if you take a piece of elemental Cr from vacuum to a normal, room temperature environment with air, does it form CrO on the surface? Or Cr2O3? Etc.
[This site][1] says that "Chromium (III) oxide, Cr2O3 is the main oxide of... |
Which form of chromium oxide is formed naturally in the atmosphere? |
Are you certain that the coupling itself isn't a radical reaction?
The bond energy of an ordinary $\ce{C-I}$ bond is in the range of $210\,\mathrm{kJ\cdot\,mol^{-1}}$, which isn't a hell of a lot. Moreover, the resulting radical of an 1,3-dicarbonyl compound is nicely stabilized. |
Today, I'm looking for how to find the 2nd perturbation to the base in Rayleigh Schrödinger Perturbation Theory (RSPT).
**SETUP**
Starting from the 2nd order perturbation:
\begin{equation}
\hat{H}^0 |n^2\rangle + \hat{V} |n^1\rangle = E_n^0 |n^2\rangle + E_n^1 |n^1\rangle + E_n^2 |n^0\rangle
\end{equa... |
I need to compare the hydrophilicity of those materials to compare contact angles of water with those materials' surfaces for surface tension measurement. Materials are:
PTFE (Teflon), PVC, PS, PVDF, Si-Wafer-Si-SiO$_x$, Parafilm and PMMA
Ordering the polarity can also work. Where can I found such a comparison? C... |
Consider the Robin boundary condition for the diffusion/heat equation $u_t=a(t)u_{xx}+f(x,t)$:
$-k(t)u_x(0,t)=h(t)u(0,t)$
or
$u_x(0,t)+\frac{h(t)}{k(t)}u(0,t)=0$
where $k(t)$ thermal conductivity and $h(t)$ heat tranfer coefficient.
My Question: Is it possible that the ratio $h(t)/k(t)$ to be constant? ... |
Today, I'm looking for how to find the 2nd perturbation to the base in Rayleigh Schrödinger Perturbation Theory (RSPT).
**SETUP**
Starting from the 2nd order perturbation in Dirac's notation:
\begin{equation}
\hat{H}^0 |n^2\rangle + \hat{V} |n^1\rangle = E_n^0 |n^2\rangle + E_n^1 |n^1\rangle + E_n^2 |n^... |
[Ionic Liquids separation of oil and sand.][1]
[1]: https://www.youtube.com/watch?v=sGDKxlW1ZoQ |
What types of chemicals/ionic liquid could perform this type of separation? |
${\beta}$-keto acids typically decarboxylate very smoothly at temperatures between 100-200°C. The mechanism involves a cyclic, 6-membered transition state that first produces an enol intermediate (see figure).
![enter image description here][1]
However in the case of your bicyclo[2.2.1] ${\beta}$-keto acid, a br... |
What is the final product of this reaction?
Here's what I have:
Does this look correct? I'm concerned because I'm used to seeing the nitrogen removed from the product (in the cases of primary amines). |
Today, I'm looking for how to find the 2nd perturbation to the base in Rayleigh Schrödinger Perturbation Theory (RSPT).
**SETUP**
Starting from the 2nd order perturbation in Dirac's notation:
\begin{equation}
\hat{H}^0 |n^2\rangle + \hat{V} |n^1\rangle = E_n^0 |n^2\rangle + E_n^1 |n^1\rangle + E_n^2 |n^... |
I have seen videos and discussions about alcohol cracking acrylic, and waterblock manufacturers reminding users to not use alcohol in cooling system with acrylic, but why is it so? |
Why does alcohol crack acrylic? |
In regards to the addition of hydrogen to alkynes, does the amount of moles of Hydrogen matter? |
For the hydrolysis of $\ce{trans-Co[(en)2Cl2]Cl}$ (and cis) we measured reaction rates via spectrophotometry. Plots of change in absorbace were used to determine the rate law and the rate for the reaction.
The lab report asks:
>Suggest another method, other than spectrophotometry, for determining the reaction rate... |
For the hydrolysis of $\ce{trans-Co[(en)2Cl2]Cl}$ (and cis) we measured reaction rates via spectrophotometry. Plots of change in absorbace $(\mathrm{ln(A-A_\infty}))$ were used to determine the rate law and the rate for the reaction. Using my data, I created the first-order plot seen below:
 :)
Before you start to model complex kinetics, begin with a simple model. If it fits, consider your job done.
**Good enough is good enough!**
(Imagine that you perform *ther... |
Spectroscopy is often the best method, since it allows for (almost) continuous monitoring of the concentration.
If that is not wanted, ask yourself:
- What is released in the hydrolysis of the complex?
Chloride would be a good guess.
- Can I take samples and perform a wet chemical analysis to determine... |
I want decrease boiling point a compound. So I need create azeotrope mixture from two or three compounds. Where can I find out how make it? |
How do I create azeotrope mixture? |
For the hydrolysis of $\ce{\mathit{trans\hyphen}Co[(en)2Cl2]Cl}$ (and *cis*) we measured reaction rates via spectrophotometry. Plots of change in absorbance were used to determine the rate law and the rate for the reaction.
The lab report asks:
>Suggest another method, other than spectrophotometry, for determining... |
How to find the second order perturbation to wave function? |
Are there any simple colorimetric tests for measuring the dissolved oxygen in salt water, which do not involve titration like in Winkler method ? i.e. Are there any chemical reagents, which when added to a salt water sample, would cause a change in the colour of the solution , giving us the measure of DO ?
Regard... |
I want to decrease the boiling point of a compound. So I need to create an azeotrope mixture from two or three compounds. Where can I find out how make it? |
I watched a ted talk (Luca Turin: The science of scent ) [https://www.youtube.com/watch?v=yzOcvINn8Iw][1] and was wondering if anyone had any examples of how to calculate vibrational spectrum's of elements? Would love to figure out how he computed these charts.
![enter image description here][2]
![enter image de... |
I'm looking at some data with substrate concentration on the x-axis and 'Kdep' on the Y. What does Kdep mean? I understand that it must be a rate of some kind but what is the significance of the '-dep' part?
Thanks |
What does Kdep stand for? |
I watched a ted talk (Luca Turin: The science of scent ) [https://www.youtube.com/watch?v=yzOcvINn8Iw][1] and was wondering if anyone had any examples of how to calculate vibrational spectra of molecules (used as fragrances)? Would love to figure out how he computed these charts.
![enter image description here][2]
... |
I know that Methane to Methanol is a common practice, but is it possible to convert Methanol back into Methane, and would it be a relatively easy process to achieve?
Thanks,
|
When water boils into water vapor, its temperature (average kinetic energy) does not change because the inputed energy is used to break its bonds. But how does that work?
Also, in a liquid, aren’t intermolecular bonds broken and reformed constantly anyway? Why does a phase change require a time interval for breaking... |
Bonding and Phase Changes? |
I'm looking at some data with substrate concentration on the x-axis and 'Kdep' on the Y. What does Kdep mean? I understand that it must be a rate of some kind but what is the significance of the '-dep' part?
Thanks
Edit:
Sorry for being vague. The data I'm looking at can be found in Figure 9 in the following ... |
I'm looking at some data with substrate concentration on the x-axis and 'Kdep' on the Y. What does Kdep mean? I understand that it must be a rate of some kind but what is the significance of the '-dep' part?
Thanks
Edit:
Sorry for being vague. The data I'm looking at can be found in Figure 9 in the following ... |
Very short question but maybe not a short answer ! As the probability of presence of electrons in a specific spatial position is defined as square of the wave function, I am wondering if there is a technique for molecular volume calculation based on the wavefunction.
Is there such a technique? |
How to calculate molecular volume from the wavefunction? |
For the hydrolysis of $\ce{\mathit{trans\hyphen}Co[(en)2Cl2]Cl}$ (and *cis*) we measured reaction rates via spectrophotometry. Plots of change in absorbance $(\ln(A-A_\infty))$ were used to determine the rate law and the rate for the reaction. Using my data, I created the first-order plot seen below:
![enter image d... |
I'm looking at some data with substrate concentration on the $x$-axis and $k_{dep}$ on the $y$. What does $k_{dep}$ mean? I understand that it must be a rate of some kind but what is the significance of the '-dep' part?
Thanks
Edit:
Sorry for being vague. The data I'm looking at can be found in Figure 9 in th... |
For the hydrolysis of $\ce{\mathit{trans\hyphen}[Co(en)2Cl2]Cl}$ (and *cis*) we measured reaction rates via spectrophotometry. Plots of change in absorbance $(\ln(A-A_\infty))$ were used to determine the rate law and the rate for the reaction. Using my data, I created the first-order plot seen below:
![enter image d... |
For the hydrolysis of $\ce{\mathit{trans\hyphen}[Co(en)2Cl2]Cl}$ (and *cis*) we measured reaction rates via spectrophotometry. Plots of change in absorbance were used to determine the rate law and the rate for the reaction.
The lab report asks:
>Suggest another method, other than spectrophotometry, for determining... |
>If cis is what's naturally found, by default it's unsaturated fat isn't it?
Both cis and trans are unsaturated. "Unsaturated" means having at least one C-C bond that is not a single bond (but instead a double or triple bond). The terms [cis and trans][1] refer to the geometry of the molecule about the double bon... |
>If cis is what's naturally found, by default it's unsaturated fat isn't it?
Both cis and trans are unsaturated. "Unsaturated" means having at least one C-C bond that is not a single bond (but instead a double or triple bond). The terms [cis and trans][1] refer to the geometry of the molecule about the double bon... |
What are the main fragmentation pathways and products of a phenyl radical cation in mass spectrometry ? I notice sometimes that there's a m/z = 51 peak after the m/z = 77 for phenyl radical cation; I assume due to loss of acetylene. |
How can we detect polyethylene from a distance?
The method should be mobile as I am thinking of employing it a mobile robot.
I have no idea about it.
Any suggestion or external link would be welcomed. |
What about $\ce{phenyl^{*+} -> Dewar\ benzene^{*+} -> cyclobutadiene^{+*} + CH2}$? |
I have a **FAT** question. This may sound cliché! Because we are in the era of "trans-fat" free, "unsaturted" food. Not to mention it's the period *where people get sicker and die faster (oh may be, the statistics weren't obvious in the past...)*.
Fats are important part of our diet and major source of energy (*the... |
I have a **FAT** question. This may sound cliché! Because we are in the era of "trans-fat" free, "unsaturated" food. Not to mention it's the period *where people get sicker and die faster (oh may be, the statistics weren't obvious in the past...)*.
Fats are important part of our diet and major source of energy (*th... |
I have a **FAT** question. This may sound cliché! Because we are in the era of "trans-fat" free, "unsaturated" food. Not to mention it's the period *where people get sicker and die faster (oh may be, the statistics weren't obvious in the past...)*.
Fats are important part of our diet and major source of energy (*th... |
What about $\ce{phenyl^{*+} -> Dewar\ benzene^{*+} -> cyclobutadiene^{+*} + C2H2}$? |
Without more experimental details, it isn't 100% clear that the small peak is exclusively derived from the phenyl radical cation. It also isn't clear that observed the "phenyl" radical cation is actually cyclic! It could be another isomer of $\ce{C6H5^{+.}}$. With benzilic acid as the ion source, it is possible that... |
For example, the rate of a chemical reaction can be expressed in $\mathrm{mol}/\mathrm{L}^{-1}/\mathrm{sec}^{-1}$. Why is it ‘−1’ and not, say, ‘−2’? Does it change the meaning if the minus is removed and we simply express the rate in $\mathrm{mol}/\mathrm{L}/\mathrm{sec}$? |
What does the ‘−1’ superscript mean in units? |
What would be the best reaction to increase the carbon chain length in an alkane? Preferably, it would be by one at a time, however, if that is not possible, just to generally increase the total length of the carbon chain (such as producing pentane from propane)
Moreover, is there a way that I can add a methyl group... |
Without more experimental details, it isn't 100% clear that the small peak is exclusively derived from the phenyl radical cation. It also isn't clear that observed the "phenyl" radical cation is actually cyclic! It could be another isomer of $\ce{C6H5^{+.}}$. With benzilic acid as the ion source, it is possible that... |
According to [chemical resistance of plexiglass acrylic][1] alcohol is not as aggressive as you mention with plexiglass acrylic.
But, we have to signal that acrylics is a big family of polymers (thermoplastics or thermosets) derived from acrylic acid, methacrylic acid or other related compounds. Plexiglass is only a m... |
Can someone explain (and preferably draw) the intermediates of this reaction?
I understand that it is a Claisen Reaction, and likely a condensat... |
From what I understand, it is the functional group attached to a structure that determines the odor it will give off, for the most part. Which explains why two similar molecules, except for their functional groups, would smell different. So, would that make it so that two different molecules with the same functional gr... |
Why might two different chemical structures smell the same? |
First question regarding corrosion of iron:
>Why is anodic area always located at nicks and scratches, where energy state is high? (does"high [potential] energy" mean unstable structure?)
![enter image description here][1]
Second questions(refer to the image):
>Why and how does $\ce{Fe^{2+}}$ move to ... |
The molecular determinants of odor perception is a disputed area in fragrance biochemistry. There are two basic theories: the "shape" hypothesis and the "vibrations" hypothesis. Luca Turin is the foremost exponent of the more controversial and less widespread "vibrations" hypothesis, but he does a good job of explain... |
Do we know what is the wavelength of the color of [Phenomelanin](http://en.wikipedia.org/wiki/Melanin#Pheomelanin)?
If not, can we use the color of Phenomelanin-rich areas, like the lips, to discern the color of Phenomelanin? |
Color of Phenomelanin? |
What determines the uniformness? Just a fun fact I am wondering.
Because I saw cyanide solutions used in electroplating. |
Why does the deposition of silver is more uniform from $[Ag(Cl)_{2}]^{-}(aq) than from $Ag^{+}$? |
At first this question might get the following response, "What are you talking about?". But really all I am kind of asking is:
> **What is the probability of us humans being disorderly?** Or in other
> words, I am kind of talking about the *Second Law of
> Thermodynamics*. But just to be clear, in how many ways ca... |
What is the probability of us being "orderly"? |
What determines the uniformness? Just a fun fact I am wondering.
Because I saw cyanide solutions used in electroplating. |
Why does the deposition of silver is more uniform from $[Ag(Cl)_{2}]^{-}(aq)$ than from $Ag^{+}$? |
According to Wikipedia what gives epoxy its holding power is apparently "ionic" interactions between the epoxy and the surface.
But I thought that epoxy was overall neutral when cured. How can it make ionic bonds with the surface it is bonded to? Or are there unprotonated alkoxides left in the epoxy which then make... |
>Can someone explain (and preferably draw) the intermediates of this reaction?
Ethoxide - a base comparable in strength to hydroxide ion - abstracts a proton from the alpha position of the ester. This forms an _enolate_ ion. Note that while protons alpha to a carbonyl center are mildly acidic - they are still not ve... |
I want to make a plasma speaker. I'm worried about the amount of ozone being produced by the ionization of the air and it possibly not being a safe amount. Even if it doesn't produce a dangerous amount, I don't like the smell of ozone. I'd like this all to be continuous. I am very unfamiliar with the chemistry here but... |
I want to make a plasma speaker. I'm worried about the amount of ozone being produced by the ionization of the air and it possibly not being a safe amount. Even if it doesn't produce a dangerous amount, I don't like the smell of ozone. I'd like this all to be continuous. I am very unfamiliar with the chemistry here but... |
Why can you not make a compound with a quaternary alpha carbon using malonic ester? |
I watched a ted talk ([Luca Turin: The science of scent][1]) and was wondering if anyone had any examples of how to calculate vibrational spectra of molecules (used as fragrances)? Would love to figure out how he computed these charts.
![enter image description here][2]
![enter image description here][3]
... |
How to calculate vibrational spectra of organic molecules? |
What determines the uniformity? Just a fun fact I am wondering about, because I saw cyanide solutions used in electroplating. |
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