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On our exam in organic chemistry, there was a question that I failed to answer correctly. The question is about the Baeyer-Villiger esterification of propiophenone or ethyl phenyl ketone:
[![1‐phenylpropan‐1‐one][1]][1]
On the exam, I answered with this structure:
[![ethyl benzoate][2]][2]
But when the exam... |
Where will the oxygen atom be inserted on the Baeyer-Villiger esterification? |
I have been testing a machine learning approach for molecular energy prediction. The current dataset that I have is QM9, which is consist of molecules with up to 9 heavy atoms. I was wondering if anyone know of the largest molecule datasets available. I will be testing ZINC, which has up to 38 atoms. Anyone knows of a ... |
I'm new to organic chemistry and having some trouble naming alcohols. I came across this molecule, I believe it's name is 3-ethyl 2-pentanol, but my online checker system is saying that I am wrong. Am I wrong, or is the online checker looking for 3-ethyl pentan-2-ol?
[![enter image description here][1]][1]
Thanks f... |
I am studying high school Chemistry, and the current unit is precipitations. The worked example states that Na2CO3 can be used to precipitate Ba2+ from a solution of BaBr2, which makes sense.
However, it does not explain why the CO3 anion should be selected, when according to the solubility table SO3 and PO4 would bot... |
Why is the CO3 anion used to precipitate Barium from BaBr2 and not another anion, such as PO4, or SO3? |
>Q: Why is the $\ce{CO3^2-}$ anion used to precipitate Barium from $\ce{BaBr2}$ and not another anion, such as $\ce{PO4^3-}$, or $\ce{SO4^2-}$?
I am studying high school Chemistry, and the current unit is precipitations. The worked example states that $\ce{Na2CO3}$ can be used to precipitate $\ce{Ba^2+}$ from a solu... |
Why is only the carbonate anion used to precipitate Barium? |
What is the dataset with the largest number of molecules? |
I have performed an experiment where I added an excess of Ca(OH)2 base to a solution consisting of 5mL of 30% hydrogen peroxide (buffered at pH 5) and a very small amount of sulfuric acid (such that the original solution of 30% H2O2 and acid was 1.7225.
I am having trouble understanding what reactions maybe occurri... |
A narrow-necked volumetric flask with a capacity of 200mL has an uncertainty of ±0.150mL so should the number of significant figures after the decimal point in my final answer be three or two? |
I have performed an experiment where I added an excess of Ca(OH)2 base to a solution consisting of 5mL of 30% hydrogen peroxide (buffered at pH 5) and a very small amount of sulfuric acid (such that the pH of the original solution of 30% H2O2 and acid was 1.7225.
I am having trouble understanding what reactions may... |
I have performed an experiment where I added an excess of Ca(OH)2 base to a solution consisting of 5mL of 30% hydrogen peroxide (buffered at pH 5) and a very small amount of sulfuric acid (such that the pH of the original solution of 30% H2O2 and acid was 1.7).
I am having trouble understanding what reactions maybe... |
I have performed an experiment where I added an excess of $\ce{Ca(OH)2}$ base to a solution consisting of 5 mL of 30 % hydrogen peroxide (buffered at pH 5) and a very small amount of sulfuric acid (such that the pH of the original solution of 30 % $\ce{H2O2}$ and acid was 1.7).
I am having trouble understanding wha... |
Below image is as available in India's Class 11 NCERT Chemistry book vol 1 Page 104. I am confused as it states all 3 bonds are kind of coordinate bonds. Should it not start with 2 covalent bonds and 3rd as coordinate bond from oxygen to satisfy carbon? There are several sites confirming my expectation. This book is in... |
Is bonds in CO is all 3 coordinate bonds or 2 covalent and 1 coordinate bonds? |
Period 1 of the periodic table contains 2 elements ($1s^1$ and $1s^2$).
Period 2 contains 8 elements ($2s^1$, $2s^2$, $2p^1$, $2p^3$, ..., $2p^6$).
By the same argument, period 3 might contain 18 elements ($3s^1$, $3s^2$, $3p^1$, $3p^3$, ..., $3p^6$, $3d^1$, $3d^2$, $3d^{10}$). Why does period 3 of the periodic t... |
Why does period 3 of the periodic table contain 8 elements instead of 18? |
I have been testing a machine learning approach for molecular energy prediction. The current dataset that I have is QM9, which is consist of molecules with up to 9 heavy atoms. I was wondering if anyone knows of available datasets that contain molecules with large numbers of heavy atoms. I will be testing ZINC, which h... |
I have been testing a machine learning approach for molecular energy prediction. The current dataset that I have is QM9, which is consist of molecules with up to 9 heavy atoms.
I was wondering if anyone knows of available datasets that contain molecules with large numbers of heavy atoms. I will be testing ZINC, whic... |
In chemistry; chirality is generally defined in 2 ways.
1. Lord Kelvin's definition: "I call any geometrical figure, or group of points, chiral, and say it has chirality, if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself" (source: 1. [chirality.org][1] , 2. Biochemistry boo... |
Is there any mathematical or logical prove for carbon with 4 different groups would be chiral? |
Why are sulfur trioxide and nitrate not isoelectronic, even though both have the same number of outer electrons? |
I thought that I already know how the Electrophilic Aromatic Substitution (EArs) for Aromatic rings work but then this reaction was shown to me and I was really sure that my professors didn't bothered teaching or even mentioning to us this reaction:
[![enter image description here][1]][1]
[1]: https://i.stack... |
I thought that I already know how the Electrophilic Aromatic Substitution (EArs) for Aromatic rings work but then this reaction was shown to me and I was really sure that my professors didn't bothered teaching or even mentioning to us this reaction:
[![enter image description here][1]][1]
In my defense, at my Uni... |
What is the physical meaning of the statements like "weight percentage of FeO in Fe"? |
I understand that if a compound has a plane of symmetry it loses its optical activity, it is very easy to understand this when we have four different substituents on a single carbon atom but when we have larger more complicated structures for example rings with many substituents which are themselves stereogenic how can... |
When ordering a diet soda (no sugar soda) in a cafe or restaurant I would like to be sure I am getting a diet soda and not a regular sugar-infested soda. Because a regular soda, is through all the sugar, far more dense than a diet soda, my idea is to use a simple hydrometer. Ideally this hydrometer would be a simple e... |
well since i'm not sure quite simply is there any possible way (apart from running a current through in the presence of a perpendicular B field) to make a small mixture of mercury magnetic so that it would respond to an applied magnetic field like from a permanent magnet? |
Based on the comments and extended chat, this is the kind of question the OP actually wanted to ask: **Consider a mixture of Fe and FeO. The total percentage (by weight) of iron is 86.638%. What is the percentage of iron metal in the mixture?**
**Answer:** For simplicity, assume exactly 100 g of the mixture. Hence t... |
For calculating mass fraction, simply divided 10/250 to get 0.04. My book says it’s wrong. Is mine the right answer?
Another one,
To calculate molality, no. moles of NaCl is 10/58.5
So $m=\frac{10}{58.5 X 250}$
$=0.684$
Again, my book says it’s wrong, and I am starting to trust is even less, but I still ne... |
That's really simple. Imagine two different vessels which are _precise mirror images_ of each other; so are all the molecules inside. Imagine that you shine polarized light on them. Being the mirror images of each other, they have to rotate light in opposite directions. But as the compound itself is symmetric, they are... |
I would like to know how this reaction actually works. I think its an ring metathesis, espececially with the Grubbs catalysator II. But I dont know how to this reaction examole really works especially with respect to enantioselectivity.
May anyone help?
[![enter image description here][1]][1]
[1]: https://i.... |
How can the free amino acid B be enantioslectively synthesitzed? |
> 10 g of NaCl is dissolved in 250 g of water. The mass fraction and molality of the solution is
For calculating mass fraction, simply divided $10/250$ to get $0.04$. My book says it’s wrong. Is mine the right answer?
Another one,
To calculate molality, no. moles of $\ce{NaCl}$ is $10/58.5$
So
$$\begin{al... |
This sounds like you were exploring work *at least related* to the work by the [Lilienfeld group][1] equally hosting a dedicated site [here][2] about data sets already used in their earlier and ongoing exploration of chemical space, programs used to work with the data, and publications.
To go considerably higher in ... |
The normal boiling point of liquid bromine is 58.2°C. At 9.3°C the equilibrium vapor
pressure of liquid bromine is 100 torr
From this data, calculate the standard state Gibbs
energy of formation of bromine vapor at room temperature, ?G? f ,298K
I tried using Clausius Clapeyron equation and get dH but I can't m... |
An orbital is a **region of space** where an electron may occupy, usually we draw a hard boundary at where the electron exist 90% of the time but it actually extends to infinity (ie. an electron can be anywhere in the universe).
Naming. In an atom, there’s principle quantum shell, sub-shell, then orbitals. “Sub orbi... |
An orbital is a **region of space** where an electron may occupy, usually we draw a hard boundary at where the electron exist 90% of the time but it actually extends to infinity (ie. an electron can be anywhere in the universe).
Naming. In an atom, there’s principal quantum shell, sub-shell, then orbitals. “Suborbit... |
Don't use a mixture, just use pure Hg. [Chill to 4.2 K][1], conveniently reached with liquid He, and all magnetic fields are excluded. Levitate on a magnet, *sans* [yogi][2].
But if you insist on using Hg at standard temperature and pressure, just use a [rotating magnetic field][3]. **N.B.** Mercury is volatile, and... |
Don't use a mixture, just use pure Hg. [Chill to 4.2 K][1], conveniently reached with liquid He, and all magnetic fields are excluded. Levitate on a magnet, *sans* [yogi][2].
But if you insist on using Hg at standard temperature and pressure, just use a [varying magnetic field][3] and *induced* current - no direct e... |
Better than a hydrometer, use an Abbe refractometer to measure the index of refraction, which varies with sugar concentration. It requires just a drop of liquid, and that small sample is unlikely to have bubbles, reducing density. You can make a [refractometer][1] to measure the sugar concentration, or you [can buy one... |
The normal boiling point of liquid bromine is 58.2°C. At 9.3°C the equilibrium vapor
pressure of liquid bromine is 100 torr
From this data, calculate the standard state Gibbs
energy of formation of bromine vapor at room temperature, ?G? f ,298K
I tried using Clausius Clapeyron equation and get dH but I can't m... |
Yes, with a couple of simplifying conditions, you can easily show that a tetrahedral carbon with 4 different chemical groups (let's call them 1, 2, 3, 4) is chiral. Let's call the atoms directly bound to the carbon L1, L2, L3 and L4.
So the first condition I will impose is that none of the groups have another tetrah... |
Generally, unless a hydroxide is in excess over a weak acid as $\ce{H2O2}$ - and it was said it is not - $\mathrm{pH}$ would be always lower than pH of the hydroxide.
$$\mathrm{pH}=\mathrm{p}K_ \mathrm{a} + \log \frac{[\ce{A-}]}{[\ce{HA}]}$$
As there is the weak acid excess over the hydroxide, the hydroxide is used ... |
Generally, unless a hydroxide is in excess over a weak acid as $\ce{H2O2}$ - and it was said it is not - $\mathrm{pH}$ would be always lower than pH of the hydroxide.
$$\mathrm{pH}=\mathrm{p}K_ \mathrm{a} + \log \frac{[\ce{A-}]}{[\ce{HA}]}$$
As there is the weak acid excess over the hydroxide, the hydroxide is used ... |
Generally, unless $\ce{Ca(OH)2}$ is in excess over a weak acid as $\ce{H2O2}$ - and it was said it was not - $\mathrm{pH}$ would be always lower than pH of the hydroxide.
$$\mathrm{pH}=\mathrm{p}K_ \mathrm{a} + \log \frac{[\ce{A-}]}{[\ce{HA}]}$$
As there is the weak acid excess over the hydroxide, the hydroxide is u... |
Generally, unless $\ce{Ca(OH)2}$ is in excess over a weak acid as $\ce{H2O2}$ - and it was said it was not - $\mathrm{pH}$ would be always lower than pH of the hydroxide.
$$\mathrm{pH}=\mathrm{p}K_ \mathrm{a} + \log \frac{[\ce{A-}]}{[\ce{HA}]}$$
As there is the weak acid excess over the hydroxide, the hydroxide is u... |
in your question formulation, you have forgotten to take into account $\ce{H2O2}$ is a weak acid.
Generally, unless $\ce{Ca(OH)2}$ is in excess over a weak acid as $\ce{H2O2}$ - and it was said it was not - $\mathrm{pH}$ would be always lower than pH of the hydroxide.
$$\mathrm{pH}=\mathrm{p}K_ \mathrm{a} + \log \fr... |
Why not to use a simple, small container with water tight cap, with adjusted mass of e.g. fine sand or salt content ?
You would adjust it to sink in diet cola and float in regular cola. Note that I am not a cola drinker,but I guess there is a rec augur is as well. So perhaps redux sugar cola should be used instead of ... |
I have noticed it frequently and decided to check with some of my peers and friends about this and they too have felt such a thing.
My question is: does water even have a taste?
And whether heating it may change the taste. |
Why does warm/hot water have a different taste as compared to cool water? |
Can I use Ascorbic acid powder as a preservative to extend the shelf life in pickled brine recipe made with vinegar? |
Can I use Ascorbic acid powder as a preservative to extend the shelf life in pickled brine recipe? |
How to calculate the standard Gibbs free energy of formation of bromine vapor at room temperature? |
in your question formulation, you have forgotten to take into account $\ce{H2O2}$ is a weak acid.
Generally, unless $\ce{Ca(OH)2}$ is in excess over a weak acid as $\ce{H2O2}$ - and it was said it was not - $\mathrm{pH}$ would be always lower than pH of the hydroxide.
$$\mathrm{pH}=\mathrm{p}K_ \mathrm{a} + \log \fr... |
Well, since I'm not sure, quite simply: Is there a possible way (apart from running a current through in the presence of a perpendicular B field) to make a small mixture of mercury magnetic so that it would respond to an applied magnetic field, like from a permanent magnet?
|
Well, since I'm not sure, quite simply: Is there a possible way (apart from running a current through in the presence of a perpendicular $\mathbf{B}$ field) to make a small mixture of mercury magnetic so that it would respond to an applied magnetic field, like from a permanent magnet?
|
in your question formulation, you have forgotten to take into account $\ce{H2O2}$ is a weak acid.
The title should rather be:
**Neutralisation between calcium hydroxide and 30% hydrogen proxide"**
Generally, unless $\ce{Ca(OH)2}$ is in excess over a weak acid as $\ce{H2O2}$ - and it was said it was not - $\mathrm{pH}... |
When potassium dichromate is being used as an oxidising agent, it gets reduced from chromium(VI) to chromium(III). Is there any way to know that or calculate that other than being familiar with general oxidation states? |
How to know dichromate is being reduced from Cr⁶⁺ to Cr³⁺? |
I was surprised to find out that the zero-point energy (ZPE) for the ground state of $\ce{BH3}$ is a few thousand $\pu{cm-1}$, because for molecules I usually work with, it's much smaller. Does anyone know the largest recorded ZPE?
I have recently asked a similar question: [What is the biggest known difference betwe... |
What is the biggest known difference between $r_e$ and $r_0$? Where $r_0$ is the average bond length of the lowest vibrational state, and $r_e$ is the location where the potential is lowest.
For a perfect harmonic oscillator, these are the same (notice that the peak probability is exactly at the minimum of the poten... |
What is the biggest known difference between rₑ and r₀? |
in your question formulation, you have forgotten to take into account $\ce{H2O2}$ is a weak acid.
The title should rather be:
**Neutralisation between calcium hydroxide and 30% hydrogen peroxide"**
Unless $\ce{Ca(OH)2}$ is in excess over a weak acid as $\ce{H2O2}$ - and it was said it was not - $\mathrm{pH}$ would be... |
Which DFT functional (KS-DFT, to be more specific) performs best at predicting macroscopic properties (density, surface tension, boiling point, relative permittivity etc.) of molecular liquids (molecular as opposed to ionic liquids or molten metals)? I'm interested in both water and commonly used organic solvents.
O... |
Which DFT functional is best for predicting macroscopic properties of molecular liquids? |
[![enter image description here][1]][1]
[![enter image description here][2]][2]
[1]: https://i.stack.imgur.com/X8uXp.png
[2]: https://i.stack.imgur.com/IRAfl.png
how the above two structure is chain isomer. because according to me what I have studied in nomenclature when a compound has both cyclic and... |
how these two structures are chain isomers? |
How the following two structures are chain isomers?
[![1: ethylbenzene; 2: 1,2‐xylene][1]][1]
According to what I have studied in nomenclature when a compound has both cyclic and straight chain, we consider that the chain as parent chain according to the following order:
1. functional group;
2. multiple bonds... |
How ethylbenzene and 1,2‐xylene are chain isomers? |
Typical motif in case of hydrogen bonds is charge transfer from electron rich acceptor Y to (usually) anti-bonding X-H σ* orbital. If so, the X-H bonding distance increases, bond weakens, stretching frequency decreases. In IR spectrum, it is visible as red shift of X-H peak and that particular peak intensifies.
Usu... |
Don't use a mixture, just use pure Hg. [Chill to 4.2 K][1], conveniently reached with liquid He, and all magnetic fields are excluded. Levitate on a magnet, *sans* [yogi][2].
Mercury in a static magnetic field, with direct current, forms a simple [homopolar electric motor][3], [creating a vortex][4]. A safer way (*s... |
When ordering a diet soda (no sugar soda) in a cafe or restaurant I would like to be sure I am getting a diet soda and not a regular sugar-infested soda. Because a regular soda, is through all the sugar, far more dense than a diet soda, my idea is to use a simple hydrometer. Ideally this hydrometer would be a simple e... |
As my previous post was a bit unclear and unspecific, I am reformulating it. First of all this is a question that I had while reading some concepts my book introduces, so this isn't a homework question in anyway. The context is: I have started reading the Thermochemistry chapter of my book, it starts explaining the con... |
K2O absorbs oxygen forming K2O2, which decomposes to K2O and O2 at 500°C. This means that K2O can absorb up to 17% its mass of oxygen. Are there other substances that exceed this ratio and release oxygen below 1000°C? |
Are there chemicals that absorb and release upon heating oxygen more efficiently than K2O? |
$\ce{K2O}$ absorbs oxygen forming $\ce{K2O2},$ which decomposes to $\ce{K2O}$ and $\ce{O2}$ at 500 °C. This means that $\ce{K2O}$ can absorb up to 17% its mass of oxygen. Are there other substances that exceed this ratio and release oxygen below 1000 °C? |
Are there chemicals that absorb and release upon heating oxygen more efficiently than potassium oxide? |
how do i answer this question? |
in your question formulation, you have forgotten to take into account $\ce{H2O2}$ is a weak acid.
The title should rather be:
**Neutralisation between calcium hydroxide and 30% hydrogen peroxide"**
Unless $\ce{Ca(OH)2}$ was in excess over $\ce{H2O2}$ - and it was said it was not - $\mathrm{pH}$ would be always signif... |
To differentiate between Mannose and Glucose , Fischer developed a series of reactions to make the aldehyde group to alcohol and terminal alcohol to aldehyde. What was this series of reactions ? |
IO3-(aq) + 5I-(aq) + 6H+(aq) → 3I2(aq) + 3H2O(l)
Why does the reaction between iodide and iodate ions have to occur in an acidic medium (H+) to form the iodine? what do the H+ ions react with?
Cheers. |
To differentiate between Mannose and Glucose , Fischer developed a series of reactions to make the aldehyde group to alcohol and terminal alcohol to aldehyde. What was this series of reactions ? Even link would be fine because I m not able to find it anywhere!! |
Potassium Sorbate have two CAS numbers - 24634-61-5; 590-00-1? - Should these not be unique? |
Why does Potassium Sorbate have two CAS numbers? - Should these not be unique? |
Potassium Sorbate has two CAS numbers - 24634-61-5; 590-00-1. Should these not be unique? |
As my previous post was a bit unclear and unspecific, I am reformulating it. First of all this is a question that I had while reading some concepts my book introduces, so this isn't a homework question in anyway. The context is: I have started reading the Thermochemistry chapter of my book, it starts explaining the con... |
As my previous post was a bit unclear and unspecific, I am reformulating it. First of all this is a question that I had while reading some concepts my book introduces, so this isn't a homework question in anyway.
The context is: I have started reading the thermochemistry chapter of my book, it starts explaining the... |
Why can't calorimetry be used to measure fast reactions? |
My understanding of the process of making mead is that you combine honey, yeast and water in an anaerobic environment. The yeast-bacteria ferments the sugar in the honey and produces ethanol (among other things?). If this is true, how come labels for mead still list e.g. 90g of sugars per litre? If I'm consuming mead, ... |
Is sugar in mead different from "regular sugar"? |
As part of some research I am doing, I want to do a head-to-head comparison of software for generating 3D atomic coordinates for molecules. Is there a list anywhere of chemical software that does this?
I was able to settle on the following constraints: freely available, or at least free for academic users; can be ru... |
I realized that liquids like petrol, kerosene and even perfumes;where combustible and then they are volatile. Could that be the reason why water is not combustible,because it is not volatile?. |
**Many volatile liquids are not combustible**
Dichloromethane (DCM) is a widely used solvent by chemists. It boils at around 40°C (the same as diethyl ether) but is not remotely combustible or flammable. HFC-124a is a refrigerant *gas* at room temperature and used to be preferred to alternatives like propane (also a... |
Volatility ( even if by thermal decomposition ) is the necessary, but not sufficient condition for liquids to be combusted, forming a flame.
Liquid helium is the most volatile liquid ever, but there is no way to burn it ( chemically ).
BTW water is volatile as well, more than the diesel fuel.
I am curious, what woul... |
**Many volatile liquids are not combustible**
Dichloromethane (DCM) is a widely used solvent by chemists. It boils at around 40°C (the same as diethyl ether) but is not remotely combustible or flammable. Ether is both very volatile and very flammable, so much so that most labs would prefer not to have it used anywhe... |
I have run calculations that predict atomic configurations. As a simple example, in a system that contains H and O, I might get a list like:
Configurations for the O atom
O H
0 2
2 6
This would tell me that in my system, there's one O atom bonded to two H atoms and there's also a molecule made... |
Software that determines whether a molecule can exist and draw it from a formula? |
I hope I understand you correctly.
For small size molecules, you can use the [Avogadro][1] program. For large systems (I use it with 40K atoms) molecules I would use [VMD][2]. If you want to generate better-looking figures I would use [Chimera][3] or [PyMol][4] which has a free version. Also, there is a very nice tria... |
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