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Why is benzenediazonium fluoroborate stable at room temperature and insoluble in water? |
See here: http://www.ochempal.org/index.php/alphabetical/s-t/snar-mechanism/
I am confused as to why this convoluted mechanism occurs. It seems as though we simply create an anion when the hydroxide attacks in order to quench it directly after by pushing out the chloride. Why does the hydroxide not push out the chlo... |
Why does the SnAr reaction proceed by the Mesenheimer complex? |
I am studying SNAr mechanism from [this webpage][1]. I am confused as to why this convoluted mechanism occurs. It seems as though we simply create an anion when the hydroxide attacks in order to quench it directly after by pushing out the chloride. Why does the hydroxide not push out the chloride in a typical substitut... |
From [Maximilian Scheurer, Peter Rodenkirch, Marc Siggel, Rafael C. Bernardi, Klaus Schulten, Emad Tajkhorshid and Till Rudack Biophysical Journal, Volume 114, Issue 3, 577-583][1]:
> One of the most relevant molecular properties that can be investigated
by all-atom MD simulations is the time-dependent evolution of... |
What are time-dependent evolution of the complex noncovalent interaction networks and why are they important? |
In other words, is an element such as Feynmanium the last chemical element that can physically exist on a planet such as Earth? |
What are the consequences of having an element with an atomic number above 137? |
After a bit of research on benzenediazonium fluoroborate, I came up with an (complete?) answer although it is based on some approximation and/or speculations.
----------
Benzenediazonium fluoborate is an versatile organic salt used to create various other organic compounds like by helping to introduce aryl, aryla... |
From [Maximilian Scheurer, Peter Rodenkirch, Marc Siggel, Rafael C. Bernardi, Klaus Schulten, Emad Tajkhorshid and Till Rudack Biophysical Journal, Volume 114, Issue 3, 577-583][1]:
> One of the most relevant molecular properties that can be investigated
by all-atom MD simulations is the time-dependent evolution of... |
What is time-dependent evolution of the complex noncovalent interaction networks and why they are important? |
In most, if not all, general chemistry books, you will find that in from constant volume calorimeters, $\Delta H = \Delta U + RT \Delta n_g$, which is, of course derived from $H = U + PV$.
My question is, given that the measured quantity is the change of temperature of the calorimeter, how can we assume that $T$ is... |
Bomb calorimeter approximations? |
In what approximations, if any, can we assume a constant temperature in a Bomb calorimeter? |
> What if this unknown material produce part of the energy stated in the problem?
It would be stated in the problem that the amount of heat that the unknown material produced.
> The standard molar enthalpy is measured under standard conditions (1 atm, 25°C). However, the condition inside the bomb calorimeter is ... |
To generalize the problem, I will just say:
> 5 gram of impure ethanol (or any other type of combustible material) is placed inside a bomb calorimeter where volume is constant. If the combustion produces a certain amount of energy, how should I find the mass in gram of pure ethanol contained in that quantity of im... |
Is this a valid method to find percentage of pure ethanol in an impure sample? |
In most, if not all, general chemistry books, you will find that in from constant volume calorimeters, $\Delta H = \Delta U + RT \Delta n_g$, which is, of course derived from $H = U + PV$.
My question is, given that the measured quantity is the change of temperature of the calorimeter, how can we assume that $T$ is... |
In most, if not all, general chemistry books, you will find that in from constant volume calorimeters, $\Delta H = \Delta U + RT \Delta n_\mathrm{g}$, which is, of course derived from $H = U + PV$.
My question is, given that the measured quantity is the change of temperature of the calorimeter, how can we assume th... |
**Both diamond and graphite are covalent networks and are both made entirely from carbon, but why does diamond have a three dimensional network of strong covalent bonds which makes it hard, whereas graphite has flat layers of carbon atoms which makes it a weak object and breakable.**
Isn't it weird when you think ab... |
Why do diamond and graphite have different structures, when they are both composed of carbon? |
In a calculation of for example a Li-Atom in a DZ basis we have 4 MO.
For the alpha string (containing two electrons), that means we have for a FCI calculation the determinants:
|12>, |13>, |14>, |23>, |24>, |34> (electrons in MO 1 and 2, 1 and 3 and so on).
If I wanted to do a truncated CI calculation (CIS for... |
In a calculation of for example a Li-Atom in a DZ basis we have 4 MO.
For the alpha string (containing two electrons), that means we have for a FCI calculation the determinants:
|12>, |13>, |14>, |23>, |24>, |34> (electrons in MO 1 and 2, 1 and 3 and so on).
If I wanted to do a truncated CI calculation (CIS for... |
**Chemical structures are a tradeoff of several factors, including the conditions on how they were formed.**
The stability of any given chemical structure depends on the ease with which any specific reaction can turn it into something else. Both graphite and diamond are very stable structures which basically means t... |
Making some researches to answer my last [post][1], I found this [article][2].
It explains that when a piece of zinc and a piece of copper are connected with a conductor, since copper is more elctronegative than zinc, electrons start to flow form zinc to copper till too many electrons has reached the piece of copper... |
Do some electrons transfer if I connect with a conductor 2 solid pieces of 2 different elements with different electronegativity? |
**Point 3)**
Why some electrons are $\mathrm{\sigma}$-bonding, $\mathrm{\pi}$-bonding or non-bonding is easier to understand if you first think about the orbitals involved. I'll discuss it in terms of hybridisation.
The central $\ce{C}$ atom has an $\mathrm{sp^2}$ hybridisation (corresponding to a trigonal planar... |
This question is a follow up of another [thread][1], where we are discussing Theresa May's accusation of the Russian government which is supposedly behind the recent chemical attack in the UK.
Soon after the attack the UK implemented a chemical analysis which again supposedly shows that this compound can be produced... |
There is really more than one question here: one is whether identifying a chemical requires the ability to make it; the other is whether the UK can reliably identify Russia as the manufacturer of the nerve agent.
The first question has a simple answer: there are plenty of known chemical structures that chemists don'... |
**Chemical structures are a tradeoff of several factors, including the conditions on how they were formed.**
The stability of any given chemical structure depends on the ease with which any specific reaction can turn it into something else. **Both graphite and diamond are very stable structures** which basically mea... |
From [Maximilian Scheurer, Peter Rodenkirch, Marc Siggel, Rafael C. Bernardi, Klaus Schulten, Emad Tajkhorshid and Till Rudack Biophysical Journal, Volume 114, Issue 3, 577-583][1]:
> One of the most relevant molecular properties that can be investigated
by all-atom MD simulations is the time-dependent evolution of... |
What is "time-dependent evolution of the complex noncovalent interaction networks" and why this is important? |
**Chemical structures are a tradeoff of several factors, including the conditions on how they were formed.**
The stability of any given chemical structure depends on the ease with which any specific reaction can turn it into something else. **Both graphite and diamond are very stable structures** which basically mea... |
> What is the major product when cyclohexene-1,2-dicarboxylic acid is electrolysed?
My try:
[![enter image description here][1]][1]
I got 2 cases but I am unable to decide which product is major, and need help here.
[1]: https://i.stack.imgur.com/hZfQt.jpg |
We were looking at the factors that affect dynamic equilibrium today. The teacher explained how catalysts only affect the rate at which dynamic equilibrium is achieved, and not its position. My question is:
Will a catalyst specific to the forward reaction shift the position of equilibrium to favour the forward reaction... |
We were looking at the factors that affect dynamic equilibrium today. The teacher explained how catalysts only affect the rate at which dynamic equilibrium is achieved, and not its position.
My question is: will a catalyst specific to the forward reaction shift the position of equilibrium to favour the forward react... |
Turns out a similar elimination reaction had been performed the reaction proceeds the following way
>
[SOURCE](https://books.google.co.in/books?id=t63ILJENEH8C&pg=PA17&lpg=PA17&dq=1,2,3,4,5,6,7,8-octahydrobiphenylene&source=bl&ots=pxCLDMZpsZ&sig... |
Turns out a similar reaction hads been performed the reaction proceeds the following way
>
[SOURCE](https://books.google.co.in/books?id=t63ILJENEH8C&pg=PA17&lpg=PA17&dq=1,2,3,4,5,6,7,8-octahydrobiphenylene&source=bl&ots=pxCLDMZpsZ&sig=YRzhqBkBTg... |
Turns out a similar reaction has been performed the reaction proceeds via the following mechanism
>
[SOURCE](https://books.google.co.in/books?id=t63ILJENEH8C&pg=PA17&lpg=PA17&dq=1,2,3,4,5,6,7,8-octahydrobiphenylene&source=bl&ots=pxCLDMZpsZ&sig=YR... |
> What is the major product when cyclohex-1-ene-1,2-dicarboxylic acid is electrolysed?
My try:
[![enter image description here][1]][1]
I got 2 cases but I am unable to decide which product is major, and need help here.
[1]: https://i.stack.imgur.com/hZfQt.jpg |
The 13C NMR of 2-heptanone is given below:
I understand the assignments of the carbons labelled 7, 6, 4 and 1.
My question is: Why is the shift of environment 5 higher than that of 3, despite being further away from the electron withdrawing car... |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/UfYnn.jpg
Here why isn't the phenyl group attacking the carbonyl carbon? Isn't the first step in addition of grignard reagent the attack by the carbanion on the carbonyl carbon ? |
By alcohol, I assume you mean ethanol. A better choice might be isopropanol (rubbing alcohol). If either ethanol or isopropanol can be mixed with your essential oil in a 10:1 ratio to give a clear solution, then the alcohol is a solvent. The water is not a solvent for the essential oil, but the alcohol might be able to... |
To generalize the problem, I will just say:
> 5 gram of impure ethanol (or any other type of combustible material) is placed inside a bomb calorimeter where volume is constant. If the combustion produces a certain amount of energy, how should I find the mass in gram of pure ethanol contained in that quantity of im... |
This figure from this [reference (p. 170).][1] might help you visualize things. [![enter image description here][2]][2]
As you can see, the stereochemistry is given by electronic repulsion between the carbonyl group and the incoming aldehyde.
[1]: https://books.google.com/books?isbn=0471465240
[2]: https://i... |
After a bit of research on benzenediazonium fluoroborate, I came up with an (complete?) answer although it is based on some approximation and/or speculations.
----------
Benzenediazonium fluoborate is an versatile organic salt used to create various other organic compounds like by helping to introduce aryl, arylazo... |
Given that K<sub>a</sub> values are determined by the position of equilibrium for a species such as HCl where K<sub>a</sub> = ([H+][Cl-]) / [HCl], I was wondering whether it would be possible to work out K<sub>a</sub> values using 'Solubility in Water' values. For example where HCl has a value of 720g/L in water at 20 ... |
Given that K<sub>a</sub> values are determined by the position of equilibrium for a species such as HCl where K<sub>a</sub> = $\frac{{[H^{+}]}{[Cl^{-}]}}{[HCl]}$, I was wondering whether it would be possible to work out K<sub>a</sub> values using 'Solubility in Water' values. For example where HCl has a value of 720g/L... |
I want to identify the correct IUPAC name for this compound:
[![enter image description here][1]][1]
I would say this is **2-methyl-5-(methylethyl)-5-(1-methylpropyl)-nonane**. However, the solution manual says that it is **2-methyl-5-(1-methylethyl)-5-(1-methylpropyl)-nonane**.
I don't understand why the fi... |
IUPAC nomenclature: redundant index? |
Given that K<sub>a</sub> values are determined by the position of equilibrium for a species such as HCl where K<sub>a</sub> = $\ce{\frac{{[H^{+}]}{[Cl^{-}]}}{[HCl]}}$, I was wondering whether it would be possible to work out K<sub>a</sub> values using 'Solubility in Water' values. For example where HCl has a value of 7... |
[![enter image description here][1]][1]
I made the following attempt to solve this question.However I don't know how to find final pressure.I don't know how to find final temperature for both sides.Can you give me a hint?
[![enter image description here][2]][2]
[1]: https://i.stack.imgur.com/DTxkr.jp... |
Turns out a similar reaction has been performed, the reaction proceeds via the following mechanism
>
[SOURCE](https://books.google.co.in/books?id=t63ILJENEH8C&pg=PA17&lpg=PA17&dq=1,2,3,4,5,6,7,8-octahydrobiphenylene&source=bl&ots=pxCLDMZpsZ&sig=Y... |
In the case of the reaction 2NO2 <--> N2O4 at equilibrium and considering Le Chatelier's principle, if we add more NO2, the pressure of NO2 will increase acutely and then begin to decrease until the system reaches its new equilibrium. Why is the new equilibrium have a higher pressure of NO2 than the original equilibriu... |
I understand that to create a molecular orbital diagram, the following rules are supposed to be met:
1. number of A.Os = number of M.Os
2. Symmetry of the binding orbitals
3. Similarity in energy
They will eventually create bonding, anti-bonding, and maybe non-bonding orbitals. However, I am having trouble sta... |
What is the function of nitrobenzene as a solvent in Friedel Crafts alkylation reaction? |
Is the index 1 in the substituent name "1-methylethyl" a redundant index? |
In the case of the reaction $$\ce{ 2NO2 <=> N2O4}$$ at equilibrium and considering Le Chatelier's principle, if we add more $\ce{NO2}$, the pressure of $\ce{NO2}$ will increase acutely and then begin to decrease until the system reaches its new equilibrium. Why is the new equilibrium have a higher pressure of $\ce{ NO2... |
Given that $K_\mathrm{a}$ values are determined by the position of equilibrium for a species such as $\ce{HCl}$ where $K_\mathrm{a} = \ce{\frac{{[H^{+}]}{[Cl^{-}]}}{[HCl]}}$, I was wondering whether it would be possible to work out $K_\mathrm{a}$ values using 'Solubility in Water' values.
For example: $\ce{HCl}$ has... |
The total volume is constant. The air compression takes place adiabatically and reversibly, so you know the relationship between its pressure and its volume.
You are told the initial volume of the water container, the mass fractions of liquid water and water vapor, and the temperature of the saturated mixture. F... |
Turns out a similar reaction has been performed, the reaction proceeds via the following mechanism
>
[SOURCE](https://books.google.co.in/books?id=t63ILJENEH8C&pg=PA17&lpg=PA17&dq=1,2,3,4,5,6,7,8-octahydrobiphenylene&source=bl&ots=pxCLDMZpsZ&sig=Y... |
For years, I've learned that [acids taste sour and bases taste bitter][1]. Recently, I've read in ["The Beer Bible"][2] and various [beer sites][3] that the hops in beer, which are acidic, cause beer to have a bitter taste.
So my question is, is it true that the acid in hops make beer bitter? And if true, does thi... |
Why does the acid in hops make beer taste bitter? |
For years, I've learned that [acids taste sour and bases taste bitter][1]. Recently, I've read in ["The Beer Bible"][2] and various [beer sites][3] that the hops in beer, which are acidic, cause beer to have a bitter taste.
So my question is, is it true that the acid in hops make beer bitter? And if true, does thi... |
I'm learning how to apply the VSEPR theory to Lewis structures and in my homework, I'm being asked to provide the hybridization of the central atom in each Lewis structure I've drawn.
I've drawn out the Lewis structure for all the required compounds and figured out the arrangements of the electron regions, and figur... |
How to find the hybridization of an atom in a molecule? |
I'm learning how to apply the VSEPR theory to Lewis structures and in my homework, I'm being asked to provide the hybridization of the central atom in each Lewis structure I've drawn.
I've drawn out the Lewis structure for all the required compounds and figured out the arrangements of the electron regions, and figur... |
If you can assign the total electron geometry (geometry of all electron domains, not just bonding domains) on the central atom using VSEPR, then you can always automatically assign hybridization. Hybridization was invented to make quantum mechanical bonding theories work better with known empirical geometries. If you k... |
According to the first point of difference rule, second one should be correct right? |
What is the purpose of a boiling stick when heating a reaction mixture?
I read some stuff online and still dont understand how it works. Does it just ensure that the mixture will boil evenly...? If so, then what's wrong when a reaction doesn't boil evenly?
Thanks. |
Purpose of boiling stick? |
Will ferric nitrate dissolve 3d printed items? I'm wanting to etch some sterling silver, for which we use either ferric nitrate or nitric acid, and wondering about 3d printing the design straight onto the silver to form the block against the acid.
Thanks for the help Julie |
Will ferric nitrate or nitric acid dissolve polylactic acid? |
Will ferric nitrate dissolve 3D printed items? I wish to etch some sterling silver, for which we use either ferric nitrate or nitric acid, and wonder about 3d printing the design straight onto the silver to form the block against the acid. |
According to the first point of difference rule, second one should be correct right? |
What is the purpose of a boiling stick when heating a reaction mixture?
I read some stuff online and still don't understand how it works. Does it just ensure that the mixture will boil evenly? If so, then what's wrong when a reaction doesn't boil evenly? |
What is the purpose of a boiling stick when heating a reaction mixture? |
What is the purpose of a boiling stick when heating a reaction mixture?
I read some stuff online and still don't understand how it works. Does it just ensure that the mixture will boil evenly? If so, then what's wrong when a reaction doesn't boil evenly?
This is the [LibreTexts page][1] I was reading information ... |
I understand there are some properties in an organic compound that allow stereoisomerism.
- double bond can't rotate
- two double bonded carbon atoms each have two **different atoms** or **groups** attached
I'm unsure by the meaning of two different atoms / groups around on each side of the double bond.
[Example pi... |
Stereo isomerism- what does it mean by two different groups? |
I understand there are some properties in an organic compound that allow stereoisomerism.
- double bond can't rotate
- two double bonded carbon atoms each have two different atoms or groups attached
I'm unsure by the meaning of two different atoms / groups around on each side of the double bond.
![enter i... |
What is it meant by two different groups in stereoisomerism? |
The boiling point of a substance is defined as the temperature at which the vapor pressure of a liquid or solution is equal to atmospheric pressure; it does not mean that gas has started precipitating out of solution. The key here is to focus on the fact that boiling is gas precipitating out of solution in much the sa... |
Boiling chips and boiling sticks are practical solutions to problems chemists face in the lab.
When boiling liquids they often observe the the boiling does not happen evenly. Instead of a gentle warming giving gentle bubbling we find that nothing happens for a while until, suddenly, a great deal of bubbling happens ... |
I`m trying to immobilize an antibody onto the glass surface by means of GPTOMS (glycidoxypropyl trimetoxy silane). Using the same protocol (silanization in toluene) I get different results any time, what are key points to check?
Looking through literature on immobilization, I see a lot of articles where authors use ... |
Problem with epoxy silane (Random results in glass silanization). What are crucial points to look at? |
Why is a brine solution consisting of a small fraction of salt in water, more effective in melting ice on a surface, than just pure salt? |
$\hspace{6.4cm}$[![image of ethyl acetate][1]][1]
I would like to know how to name the alkyl groups connected to the above molecule. For example, would the far left alkyl group be considered a methyl ester group? Would the alkyl group bound to the oxygen be a methylene ester group?
[1]: https://i.stack.imgur... |
$\ce{Cu^2+} $ has 9 electrons and the $\mathrm d$-orbital is almost completely filled (except for 1 electron vacancy), eventually forming $\mathrm{sp^3}$ hybrid orbitals, where each $\ce{NH3}$ donates a lone pair of electrons.
But it has been found to have a square planar geometry, hence completely contradicting the... |
>Is the following reaction endothermic or exothermic and why?
$$\ce{2 AgNO3(aq) + Cu(s) -> Cu(NO3)2(aq) + 2 Ag(s)}$$
I have a feeling that it is exothermic due to the fact that it is spontaneous and will end in around 30 minutes (which I am guessing is because it will run out of energy to burn) and no source of e... |
I`m trying to immobilize an antibody onto the glass surface by means of GPTOMS (glycidoxypropyl trimetoxy silane). Using the same protocol (silanization in toluene) I get different results any time, what are key points to check?
Looking through literature on immobilization, I see a lot of articles where authors use ... |
If there is an infinite number of levels, this means that every electron can jump from as many variations as possible. Hence, why can’t every element emit every colour?
Please don’t use very complicated theory because I’ve just started my A levels. |
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 need to have real life applications. What a few real life reactions that are easy to replicate in a school chemistry lab... |
Need a solvent for a freezing point depression experiment. Acetic acid is the only one I know of, but it is not ideal due to the low freezing point depression constant. Any suggestions? |
First, a disclaimer: there is no shortage of opinion about what comprises physical or chemical changes.
[This](https://www.education.vic.gov.au/school/teachers/teachingresources/discipline/science/continuum/Pages/physchem5.aspx) page is entitled **Identifying Physical and Chemical Changes** and is intended to help... |
First, a disclaimer: there is no shortage of opinion about what comprises physical or chemical changes.
[This](https://www.education.vic.gov.au/school/teachers/teachingresources/discipline/science/continuum/Pages/physchem5.aspx) page is entitled **Identifying Physical and Chemical Changes** and is intended to help... |
For example, oxygen is neutral when it has just 6 electrons. But the pink O in the molecule pictured has 3 bonds giving it 8 electrons, a full-octet. It's more electronegative than all the atoms it's bonded to also. It would make sense if an O with a full-octet had a -2 charge since it has an extra 2 electrons.
But ... |
In periodic table, the atomic weight is more or less twice the proton number. Do neutrons naturally tend to be in similar quantity as protons? I know atomic weight weighted average of isotopes but why this more or less a trend if we move across the periodic table we find atomic weight is 2(protons) + $\epsilon$ where $... |
Why is atomic number is more or less twice the proton number for light elements? |
I did an experiment with copper sulfate where you place two copper rods in an aqueous solution of copper sulfate. You apply an electric current and copper metal builds up on the cathode. I noticed that the copper anode dissolved. Does the dissolved copper from the anode just turn into more copper sulfate? If not, what ... |
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