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Why is 2-Fluorobenzoic acid more acidic than 4-Fluorobenzoic acid despite its intramolecular hydrogen bonding? |
Here is my setup:i use $\pu{12 V}$ battery wires are copper, i use tap water with $\ce{NaHCO3}$ dissolved in it. İ connected the battery and everything went as expected but after 5 minutes bubbling stopped.İ took out the copper electrodes and saw green deposits on the anode that were blocking the current.İ think green ... |
I use $\pu{12 V}$ battery with copper wires and tap water with $\ce{NaHCO3}$ dissolved in it. I connected the battery and everything went as expected but after 5 minutes bubbling stopped. I took out the copper electrodes and saw green deposits on the anode that were blocking the current.
I think green stuff was mala... |
One of the books refer to potential energy being ordered whereas heat energy being random. Could someone explain what is ordered and random energy? |
I was reading about $pK_a$ values of 2-Fluorobenzoic acid and 4-Fluorobenzoic acid and found that the latter had a higher value which was surprising to me as I think that intramolecular hydrogen bonding should dominate all the other effects in 2-Fluorobenzoic acid as mentioned in the following figure and thus it shoul... |
I was reading about $\mathrm{p}K_\mathrm{a}$ values of 2-fluorobenzoic acid and 4-fluorobenzoic acid and found that the latter had a higher value which was surprising to me. I think that intramolecular hydrogen bonding should dominate all the other effects in 2-fluorobenzoic acid as mentioned in the following figure an... |
Why is 2-fluorobenzoic acid more acidic than 4-fluorobenzoic acid despite its intramolecular hydrogen bonding? |
In the mechanism of alcohol-ozonolysis, the intermediate molozonide adduct, which is a cyclical but symmetric molecule (shouldn't symmetry about the C-C single bond bring stability??), decomposes thermally into a ketone and a peroxy-zwitter ion, via cleavage of an O-O bond and the C-C bond. It seems unlikely, and again... |
Why is the molozonide adduct thermally unstable? |
What is the reason there is no salt bridge for this cell?
$$\ce{Pt(s) | H2(g) | HBr(aq) | AgBr(s) | Ag(s)}$$
|
Why is there no salt bridge for hydrogen–silver bromide cell? |
In the mechanism of alcohol-ozonolysis, the intermediate molozonide adduct, which is a cyclical but symmetric molecule (shouldn't symmetry about the C-C single bond bring stability??), decomposes thermally into a ketone and a peroxy-zwitter ion, via cleavage of an O-O bond and the C-C bond. It seems unlikely, and again... |
In the mechanism of alcohol-ozonolysis, the intermediate molozonide adduct, which is a cyclical but symmetric molecule (shouldn't symmetry about the C-C single bond bring stability?), decomposes thermally into a ketone and a peroxy-zwitter ion via cleavage of the O−O and C−C bonds.
However, it seems unlikely, and is... |
Is there a way to determine the number of π-electrons in a conjugated system from UV-Vis data? I am modelling the electrons as particles in an infinite box of length $L$ equal to the length of the conjugated system. I am unsure how to interpret the spectra to obtain the number of π-electrons, including the systems with... |
How to determine the number of π-electrons in a conjugated system from UV-Vis data? |
A recent article (ACS Omega 2021, 6, 8021−8027) confirms the stability of nanobubbles with theoretical principles. Nanobubbles, having a size in the range of 50-500 nm, are reported to be metastable, i.e., stable in various liquids for times ranging up to weeks. Is the inside of the bubble filled with a gaseous form of... |
What is inside nanobubbles? |
I am not sure to understand something I read in a educational journal (1)
# Introduction
Lets consider the following reversible enzyme-catalysed reversible reaction;
> $E + S \leftrightharpoons ES \leftrightharpoons E + P$
with forward rate constants $k_1$ and $k_2$ and backward rate constants $k_{-1}$ and ... |
Not a chemist, but from a chemical formula perspective, how hard would it be to create acetone from glycerol and 2(H+)?
2(H+) + C3H8O3 <====> 2(H2O) + C3H6O
Has anyone ever heard of this being attempted? If it isn't possible, why? |
Not a chemist, but from a chemical formula perspective, how hard would it be to create acetone by acidifying glycerol?
$$\ce{C3H8O3 + 2 H+ <=> C3H6O + 2 H2O}$$
Has anyone ever heard of this being attempted? If it isn't possible, why? |
I am not sure to understand something I read in a educational journal (1)
# Introduction
Lets consider the following reversible enzyme-catalysed reversible reaction;
$$E + S \leftrightharpoons ES \leftrightharpoons E + P$$
with forward rate constants $k_1$ and $k_2$ and backward rate constants $k_{-1}$ and... |
What decides whether you call something random versus ordered (or heat or work) is how much information you have to describe the system. The idea is that describing the detailed motion (positions and momenta) of a very large numbers of things, on the order of $\pu{6E23}$ particles (moles of stuff), and on top of that ... |
It is well known that peptides are synthesized by a so called "condensation" reaction between an amine and a carboxylic acid group to form the final amide moiety (because it releases water). In its general form, it resembles the picture below.
[![Depicted here][1]][1]
[1]: https://i.stack.imgur.com/NA3Fv.png
... |
this answer shows that [dimerization is a synthetic method](https://chemistry.stackexchange.com/a/34009/101483)
On wikipedia, [1-octene is showed to made from numerous dimerizations or a tetramerization.](https://en.wikipedia.org/wiki/1-Octene)
When I read that [piperazine $\ce{C4H10N2}$ is made with ammoniation o... |
Examples to show how useful or not useful of dimerization, trimerization, tetramerization and their likes in synthesizing alkenes and other compounds? |
I'm thinking of that type of glue that you apply to both sides, let dry and then press together. Like [this][1]. It seems counter intuitive.
Other glues behave in the opposite manner, and get less sticky as they dry. So does duct tape. So does jam. And actually everything else I can think of. The container recommend... |
Why does contact glue get stickier (to itself) as it dries? |
What is the product of 2,2-dimethyl-1,3-dioxane when it is mixed with H2, Raney Ni? |
I can calculate the vapor pressure of the Acetone at any given temperature using the Antoine equation. Is it possible to find the normal boiling temperature of the Acetone?
(It has to be done by just using the vapor pressure at various temperatures without using any constant specific to Acetone) |
How to find normal boiling temperature if vapor pressure is known in any temperature? |
Here is my program for calculating the vapor pressure of the Organic Chemicals using Antoine's Equation:
def Psat_Antoine(temp,A,B,C):
return numpy.exp(A-B/(temp+C))
A_Actn, B_Actn, C_Actn = 14.31451662590449, 2756.0411263712826, 228.03915724014055
A_Mthnl, B_Mthnl, C_Mthnl = 16.57209916... |
How to find the normal boiling temperature if vapor pressure at any temperature is the only thing that can be usable? |
In the mechanism of alkene-ozonolysis, the intermediate molozonide adduct, which is a cyclical but symmetric molecule (shouldn't symmetry about the C-C single bond bring stability?), decomposes thermally into a ketone and a peroxy-zwitter ion via cleavage of the O−O and C−C bonds.
However, it seems unlikely, and is ... |
Since entropy increases when temperature increases, the entropy of surroundings increases during an exothermic reaction. When I apply the same logic, it seems like the entropy of a chemical system increases in an endothermic reaction. Is this true? |
Does the entropy of a chemical system increase in an endothermic reaction? |
I read all salts from sodium salts form colorless solutions unless the anion is colored. Can someone explain? |
Do all salts of sodium form colorless solutions? |
According to my textbook, in steam distillation the liquid books when the sum of vapor pressure die to organic liquid and that due to water becomes equal to the atmospheric pressure. Why? I did not understand. |
According to my textbook, in steam distillation the liquid boils when the sum of vapor pressure due to the organic liquid and that due to water becomes equal to the atmospheric pressure. Why? I did not understand. |
I am running an electrolysis between two silver electrodes.
The “electrolyte” is deionized water.
Ions are still formed as the CO2 of the air generates enough ions for a few µA of current.
During the electrolysis the ions are converted to metallic silver nanoparticles due to strong ultraviolet radiation.
I have t... |
I am running an electrolysis between two silver electrodes.
The “electrolyte” is deionized water.
Ions are still formed as the CO2 of the air generates enough ions for a few µA of current.
During the electrolysis the ions are converted to metallic silver nanoparticles due to strong ultraviolet radiation.
I have t... |
[![The compound is given in the image][1]][1]
[1]: https://i.stack.imgur.com/qLies.png
What is the double bond equivalence of the given compound? The given answer is 14 (8 pi electrons and 6 rings = 14 DBE). But why isn't the lone pair on nitrogen considered?? The lone pair on nitrogen involves in resonance w... |
What is the double bond equivalence of the following compound? |
The [eMolecules][1] page for example offers [a complete dataset][2] containing ~26 million structures. They're providing it either as a 300 MB [SMILES][3] archive or 6 GB SDF archive (1.5 GB and 50 GB uncompressed respectively).
Does the SDF file contain any information about the chemical structu... |
Does the SDF format have any benefit over SMILES? |
How carbon nanotube sensors works?
Is the protein (or chemical compound used as part of the sensor) placed inside the tube or where is it placed? and how is the technology used to place the protein there?
In the [National Geographic][1] magazine we can read (speaking about a young inventor)
> he could interweave... |
How carbon nanotube sensors works? |
I need to prepare the $\pu{1M}$ solution of sodium crotonate, however, I don't have one in lab, but I do have sodium hydroxide and crotonic acid.
Thus, I calculated that for $\pu{100 mL}$ of $\pu{1M}$ solution I need: ~$\pu{4g}$ of $\ce{NaOH}$ and ~$\pu{8.6g}$ of crotonic acid. After preparation of solution (approx... |
This is my first post here, so please correct any mistakes related to my question (if any).
I'm just now learning about the Fourier transform, which seems like a pretty useful tool, and I know it has uses in spectroscopy (e.g. FTIR) since that is what google shows when searching for applications of Fourier transfo... |
Non spectroscopy related uses of fourier/laplace transform in chemistry? |
As the title says, what does "the natural bond angle θ<sub>0</sub>" mean in the context of Universal Force Field (UFF) potential energy calculation? The reference appears in section D. Angular Distortions, 1. Angle Bend). The article also talks about "natural bond length" (Section C. Bond Stretch).
I am curious abou... |
What does "the natural bond angle θ<sub>0</sub>" mean in the context of Universal Force Field (UFF) potential energy calculation? |
What does "the natural bond angle" mean in the context of Universal Force Field (UFF) potential energy calculation and how are bond angles calculated? |
For the principle «what is small, gets large; what is large, gets small» when applying Fourier transformation and inverse Fourier transformation, it is one important tool in crystallography to relate between the regular arrangement of molecules in crystals at Angstrom scale, and the intensity recordings on film (old sc... |
I was asked to find the lowest $C=O$ bond strength among $[Mn(CO)_{6}]^{+}$ , $Fe[(CO)_{5}]$, $[Cr(CO)_{6}]$ and $[V(CO)_{6}]^{-}$.
I thought the C=O bond strength would be lowest in $[V(CO)_{6}]^{-}$, since the negative charge meant that the metal ($V$) had an excess of electrons hence the metal-carbon back-bonding... |
> Find the weakest $\ce{C=O}$ bond among $\ce{[Mn(CO)6]+},$ $\ce{Fe[(CO)5]},$ $\ce{[Cr(CO)6]}$ and $\ce{[V(CO)6]-}.$
I thought the $\ce{C=O}$ bond strength would be lowest in $\ce{[V(CO)6]-}$ since the negative charge meant that vanadium had an excess of electrons, hence the metal-carbon back-bonding would be the st... |
I am looking at a set of results showing a directly proportional relationship for an increasing maximum absorption wavelength (UV-Vis spectra) with increasing donor number of solvent ligands. The complex has a $\ce{Cu^2+}$ centre with $\mathrm{d^9}$ electronic configuration. Assuming a tetragonal configuration, how doe... |
Working from the thermodynamic identity
$$\Delta{S} = -\left(\frac{\partial{\Delta{G}}}{\partial{T}}\right)_p,$$
is it allowed to integrate both sides to obtain an expression derived from the Nernst equation
$$E_\mathrm{cell} = \frac{T\,\Delta S}{zF}?$$
Can one plot the results and obtain $\Delta S$ from th... |
What is the product of reaction between 2‐cyclobutyl‐2‐isopropyl‐1,3‐dioxane and hydrogen with Raney nickel? |
> Given the following thermodynamic data at $\pu{298 K}:$
>
> $$
\begin{array}{lrrr}
\hline
\text{Compound} & \Delta_\mathrm{f}H^\circ/\pu{kJ mol^-1} & S^\circ/\pu{J K^-1 mol^-1} & C_p^\circ/\pu{J K^-1 mol^-1}\\
\hline
\ce{HI(g)} & 26.5 & 206.6 & 29.2 \\
\ce{I2(g)} & 62.4 & 260.7 & 36.9 \\
\ce{H2(g)} & 0.0 & 1... |
How to find the equilibrium constant under non-standard conditions? |
Consider the ability to predict something in a detailed manner as synonymous with "ordered", and the inability synonymous with "random". For instance, a perfect crystalline solid is more ordered than a gas because given the position of one particle in a solid and a few lattice constants we can derive to a good extent t... |
If FeSO4.7H2O is dissolved in an acidic environment, for example in methanoic or ethanoic acid, would that prevent it from getting oxidized if an oxidizing agent like bromine water was added to it? If so, how? Since this is not examining oxidation with respect to air or oxygen. |
How do acids prevent ferrous sulphate from getting oxidised? |
Consider the ability to predict something in a detailed manner as synonymous with "ordered", and the inability synonymous with "random". For instance, a perfect crystalline solid is more ordered than a gas because given the position of one particle in a solid and a few lattice constants we can derive to a good extent t... |
If $\ce{FeSO4.7H2O}$ is dissolved in an acidic environment, for example in methanoic or ethanoic acid, would that prevent it from getting oxidized if an oxidizing agent like bromine water was added to it? If so, how? Since this is not examining oxidation with respect to air or oxygen. |
How do acids prevent ferrous sulfate from getting oxidised? |
When atomic orbitals combine in phase (0°) we get bonding molecular orbitals, and when they combine with opposite phases (180°) we get antibonding molecular orbitals.
Why can't atomic orbitals combine in phases between 0 and 180? |
Can atomic orbitals combine in a manner intermediate between bonding and antibonding? |
If $\ce{FeSO4.7H2O}$ is dissolved in an acidic environment, for example in 0.05 M aqueous solutions of methanoic or ethanoic acid, would that prevent it from getting oxidized if an oxidizing agent like bromine water was added to it? If so, how? Since this is not examining oxidation with respect to air or oxygen. |
In lecture I was taught that, in a galvanic cell at standard conditions, platinum is often used as an inert electrode when the species being oxidized or reduced exists only in solution, because platinum is "inert," which means it is very stable at and resists reduction or oxidation. This concept confuses me for two rea... |
How can platinum function as an "inert electrode" while having a standard reduction potential of 1.2? |
The Fourier Transform is important in many applications beyond spectroscopy, for instance in computational and theoretical chemistry. One example encountered in learning chemistry is in quantum theory. The FT is intimately related to the Heisenberg Uncertainty principle (for instance for position-momentum). You might ... |
The Fourier Transform is important in many applications beyond spectroscopy, for instance in computational and theoretical chemistry. One example encountered in learning chemistry is in quantum theory. The FT is intimately related to the Heisenberg Uncertainty principle (for instance for position-momentum). You might ... |
In the section Brønsted-Lowry acid and base theory from Khan Academy:
>[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/fjV8R.png
I don't understand how HBr is donating a proton to LiOH, cause I think it would produce something like "LiOH2," but the reaction gives LiBr.
So where is my... |
"HBr is donating a proton to LiOH" Why don't it produce LiOH2? |
I'm particularly looking in the context of alkyl lithiums compared to vinyl-lithiums and alkynyl-lithiums.
Why is it that shifting from sp3 to sp2, and even further to sp carbanions, reduces the basicity and allows for nucleophilic attack to occur preferably?
I understand that a greater s-character means the nega... |
Why does hybridisation decrease basicity and allow for preferential nucleophilic attack? |
> I think it would produce something like "LiOH2,"
You are missing the charge. It should be something like $\ce{LiOH2+}$, which is an unconventional way of writing $\ce{Li+(aq) + H2O(l)}$.
> So where is my misunderstanding?
You have to get use to interpreting the (aq) designation after ionic compounds. To hel... |
This is probably a basic question. According to the fine structure formula (Sommerfield formula), the energy depends only on $n$ and the absolute value of the total angular momentum $j$. Now, in the absence of magnetic field, there are two spectral lines for the SOdium atom $D1$ and $D2$. I am confused about the origin... |
This is probably a basic question. According to the fine structure formula (Sommerfield formula), the energy depends only on $n$ and the absolute value of the total angular momentum $j$. Now, in the absence of magnetic field, there are two spectral lines for the Sodium atom $D1$ and $D2$. I am confused about the origin... |
This is probably a basic question. According to the fine structure formula [see here](https://en.wikipedia.org/wiki/Fine_structure#Exact_relativistic_energies)(Sommerfield formula), the energy depends only on $n$ and the absolute value of the total angular momentum $j$. Now, in the absence of magnetic field, there are ... |
According to the [fine structure formula for exact energies](https://en.wikipedia.org/wiki/Fine_structure#Exact_relativistic_energies) (Sommerfield formula)
$$E_{jn} = -m_\mathrm{e}c^2\left[1 - \left(1 + \left[\frac{\alpha}{n - j - \frac 1 2 + \sqrt{\left(j + \frac 1 2\right)^2 - \alpha^2}}\right]^2\right)^{-1/2}\ri... |
> Sketch the Lewis structure of *all trans-2,4,6-octatrienoic acid*.
>
> (a) Consider the delocalized π electrons. Employ the particle-in-a-box model. Drawing on your knowledge about the occupation of orbitals in atoms what is the highest occupied state? Sketch the occupation of the energy levels with electrons using... |
Problem: I am a physics and engineering major going to work for an engineering company this summer. My boss wants me to do a comprehensive review of hydrogen fuel cells and report back on the cutting-edge advancements and potential future advances. I tried checking out some papers on hydrogen fuel cells on the web of s... |
>Why is the molozonide adduct thermally unstable?
The molozonide adduct (1,2,3-trioxalane; the initial adduct by 1,3-dipolar cycloaddition of alkene and ozone) is thermally unstable because it contains two weak $\ce{O-O}$ bonds (Ref.1). Mechanistic studies reveal that the ozonide (1,2,4-trioxalane) is formed by a se... |
>Why is the molozonide adduct thermally unstable?
The molozonide adduct (1,2,3-trioxalane; the initial adduct by 1,3-dipolar cycloaddition of alkene and ozone) is thermally unstable because it contains two weak $\ce{O-O}$ bonds (Ref.1). Mechanistic studies reveal that the ozonide (1,2,4-trioxalane) is formed by a se... |
What would be the product (B) in the following sequence of reaction? |
In lecture I was taught that, in a galvanic cell at standard conditions, platinum is often used as an inert electrode when the species being oxidized or reduced exists only in solution, because platinum is "inert," which means it is very stable at and resists reduction or oxidation. This concept confuses me for two rea... |
I have a set of data I would like to use the Birge- Sponer extrapolation with but the data is the wavenumbers of the bands in the vibrational- electronic spectrum of a diatomic molecule for v'=0,1,2,3,4,5,6. I thought the y axis should have the wavenumber values given as they are (in cm^-1) but the values given increas... |
Should Birge- Sponer plots always have a negative gradient? |
I was confused as to why the hydrolysis of ATP to AMP and pyrophosphate was more energetic than hydrolysis to ADP and inorganic phosphate. Especially since pyrophosphates are more unstable than inorganic phosphates?
My only guess was that the pyrophosphate undergoes further hydrolysis to inorganic phosphates due to ... |
Why is the Hydrolysis of ATP to AMP more energetic than the Hydrolysis of ATP to ADP? |
I have a set of data I would like to use the Birge–Sponer extrapolation with, but the data is the wavenumbers of the bands in the vibrational-electronic spectrum of a diatomic molecule for $v' = 0, 1, 2, 3, 4, 5, 6.$
I thought the $y$ axis should have the wavenumber values given as they are (in $\pu{cm^-1}),$ but th... |
Should Birge–Sponer plots always have a negative gradient? |
Why is the hydrolysis of ATP to AMP more energetic than the hydrolysis of ATP to ADP? |
**Synposis**
I'm in general chemistry, and I was wondering how ionic species crystallize and form the shapes they do, specifically in regard to the Struvite precipitate $\ce{MgNH_4PO_4. 6H_2O}$.
Deconstructing the ionic species, we get $\ce{NH_4^+}$, which does not have a dipole moment (I think), $\ce{PO_4^{3-}}... |
Struvite Crystals: How does it form? |
> I think it would produce something like "LiOH2,"
You are missing the charge. It should be something like $\ce{LiOH2+}$, which is an unconventional way of writing $\ce{Li+(aq) + H2O(l)}$.
> So where is my misunderstanding?
You have to get used to interpreting the (aq) designation after ionic compounds. To he... |
This is a fun one, and a common question in this course. First, as you say, H and Br are lost by anti elimination, since they helpfully tell you base and E2 are involved. That means the H and Br are lost from opposite faces of the future double bond, leaving us with a trans intermediate that has a mirror plane (the p... |
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