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How to use dispersion correction with M06-2x in Gaussian 09 or 16? |
_____________________________
Operatively:
A plane of symmetry in a 2-D projection of a cyclohexane is a sufficient condition.
Alternatively, and lengthy, you conduct an analysis involving conformers but *not limited to the flipping of the ring*, that means you must let the chloromethyl rotate, in your example.
______... |
I'll try and answer your question, but a "full" answer would take a book.
Given the reaction:
$$\ce{aA + bB <=> cC + dD}$$
Then assuming an [elementary reaction](https://en.wikipedia.org/wiki/Elementary_reaction) in the gaseous state the concentration equilibrium constant always has products over reactants an... |
Overall I agree with Alchimista's answer, though I think it might be quite complex to grasp, seeing the comments that followed it.
If it helps, here's my down-to-earth version, which in fact covers chirality in general, not just cyclohexanes.
The 'executive summary' of my answer would be: not only it is correct t... |
The initial state of your system consists of 4 moles of Fe(s) and 3 moles of water vapor at 298K and 1 bar in separate containers. The final state of your system consists of 2 moles of Fe2O3(s) and 3 moles of H2(g) at 298K and 1 bar in separate containers. The $\Delta H^0$ and $\Delta S^0$ correspond to a process for... |
***Update
Some questions I am considering to try to answer this question;
- When dissolving the powder in acetic acid, which ions are present?
- From what I've read, I haven't found any acetate salts that are not soluble in water. What other metal salts could be forming that aren't soluble?
- Which ions might ... |
[![enter image description here][1]][1]I have looked through articles and closest I feel is in this question there will be a nucleophilic aromatic substitution. Now A lot of questions are available where There is a halogen and OMe group substitutes the halogen.
My take on this is maybe due to SIR effect (Steric inhi... |
When 1,3 dimethy 2,5 Dintrobenzene is the substrate what would happen if NaOMe/MeOH is given to this compound? |
[![enter image description here][1]][1]
In the reactant due to $\ce{H+}$ ion a positive charge will be created by removing water in place of the rightmost $-\ce{OH}$. But then how it will give such product. I cant see any way to make the cyclic pentane first. There would be a Pinacol-Pinacolon Rearrangement but how ?
... |
_____________________________
Operatively:
A plane of symmetry in a 2-D projection of a cyclohexane is a sufficient condition.
Alternatively, and lengthy, you conduct an analysis involving conformers but *not limited to the flipping of the ring*, that means you must let the chloromethyl rotate, in your example.
______... |
Is isopropanol (or 2-propanol) a better solvent than ordinary propanol (or n-propanol, or 1-propanol)?
This is strongly implied, from what I have read, but I can't seem to find a place that distinctly says so....
Several places have said that mixing well with a wide range of substances makes it a better germ-kill... |
Why is isopropyl alcohol (isopropanol) used in rubbing alcohol instead of 'regular' propanol? |
Upon using aluminium Electrodes for a concentrated solution of NaCl, i conducted electrolysis on the solution for nearly 4-5 hours. There was definitely a gas possibly hydrogen being evolved at the cathode. The anode was also dissolving at a fast rate. After the electrolysis i evaporated the remainder of the water and ... |
I learnt that stable colloid forms due to the negative charges of H2O molecules are facing the solution, hence colloid particles repel each other.
[![][1]][1]
[1]: https://i.stack.imgur.com/QQnvp.jpg
I also learnt that colloids are destroyed upon the addition of an electrolyte, but I would like to know ... |
How does adding electrolyte destroy colloids? |
Let me tell what I understand of the concepts on which the question is based first.
Heat is a flow of energy that takes place due to a temperature gradient.
When doing reversible isothermal expansion of an ideal gas, even though there is no net change in the system's temperature before and after the process, ea... |
Let me tell what I understand of the concepts on which the question is based first.
Heat is a flow of energy that takes place due to a temperature gradient.
When doing reversible isothermal expansion of an ideal gas, even though there is no net change in the system's temperature before and after the process, ea... |
I would like to buy some polyacrylonitrile (PAN) powder from GoodFellow and I have the choice between these two products:
- AN316010, quality : Copolymer (99.5% AN / 0.5% MA)
- AN316020, quality : Copolymer (93.9% AN / 5.8% MA/ 0.3 % MS)
What I do not understand is the meaning of these three acronyms. **What... |
Copolymer purity, what does AN / MA / MS mean? |
I would like to buy some polyacrylonitrile (PAN) powder from GoodFellow and I have the choice between these two products:
- AN316010, quality : Copolymer (99.5% AN / 0.5% MA)
- AN316020, quality : Copolymer (93.9% AN / 5.8% MA/ 0.3 % MS)
What I do not understand is the meaning of these three acronyms. **What... |
I learnt that micellar particles formed by ionic detergents forms due to the negative charges of H2O molecules are facing the solution, hence micellar particles repel each other.
[![][1]][1]
[1]: https://i.stack.imgur.com/QQnvp.jpg
I also learnt that micellar particles are destroyed upon the addition of... |
It is said that a catalyst speeds up the rate of a reaction but is not consumed (assuming no side reactions take place). Suppose we have the following reaction:
$$\ce{A + B <=> C} $$
catalysed by $\ce{X}$ in the following steps:
$$\ce{A + X <=> A-X} \tag{1}$$
$$\ce{A-X + B <=> C} \tag{2}$$
Each step is rev... |
Why a catalyst is not consumed in a reaction when all steps are reversible? |
It is said that a catalyst speeds up the rate of a reaction but is not consumed (assuming no side reactions take place). Suppose we have the following reaction:
$$\ce{A + B <=> C} $$
catalysed by $\ce{X}$ in the following steps:
$$\ce{A + X <=> A-X} \tag{1}$$
$$\ce{A-X + B <=> C + X} \tag{2}$$
Each step is... |
The order of ionic radii for halides and hydride:
$$\ce{F-} < \ce{Cl-} < \ce{Br-} < \ce{H-} < \ce{I-}$$
What is the reason for such large ionic radius of hydride ion? |
Why ionic radius of hydride is so large? |
I'll try and answer your question, but a "full" answer would take a book.
Given the reaction:
$$\ce{aA + bB <=> cC + dD}$$
Then assuming an [elementary reaction](https://en.wikipedia.org/wiki/Elementary_reaction) in the gaseous state the concentration equilibrium constant always has products over reactants an... |
[![enter image description here][1]][1]
I have looked through articles and closest I feel is in this question there will be a nucleophilic aromatic substitution. Now, a lot of questions are available where there is a halogen and OMe group substitutes the halogen.
My take on this is maybe due to SIR effect (steric... |
It is universally recognized that NMR measures the shielding of nuclei from magnetic fields by electrons. The electrons *move*, producing an eddy current that produces an opposing magnetic field.
It is also fairly widely said that a filled valence shell contains electrons making every possible motion within a certa... |
How do we explain NMR shielding in filled valence shells? |
> An aromatic compound (A), $\ce{C7H6Cl2}$, gives $\ce{AgCl}$ on boiling with alcoholic $\ce{AgNO3}$ solution and yields $\ce{C7H7OCl}$ on treatment with $\ce{NaOH}$. (A) on oxidation gives a mono-chlorobenzoic acid which affords one mono-nitro derivative. Find the Compound (A).
Here from $\ce{C7H6Cl2}$ we can say... |
How to identify the aromatic compound with the sum formula C7H6Cl2? |
Suppose I have a napthalene-like molecule ([attached][1]), and I would like to scan (relaxed) its aromatic dihedral (highlighted atoms). I used CGENFF to obtain its dihedral parameters as follows,
HGA4 CG2DC2 CG311 CG331 0.2000 3 0.00
As shown, the dihedral force constant is 0.2, periodicity is 3, and angle is 0.... |
How much should I scan an aromatic dihedral? |
I am looking for a chemical test for the presence of gluten: however, having looked online for such a thing, all the results seem to be about 'home testing kits' (presumably for people with a gluten intolerance). Is there a simple chemical test which can be used for a school science project (meaning that the chemicals ... |
Is there a chemical test for gluten? |
Are we limited to use only xy, yz and zx planes to check for planes of symmetry of a molecule? Because I see a plane of symmetry in the following molecule through the two shown H atoms or OH groups. I am aware of the 3D structure shown by this projection. And since this molecule is Chiral, and has enantiomeric mirror ... |
According to me <br>
<b>$MnO_{4}^{2-}$</b>→ Paramagnetic <br>
<b>$MnO_{4}^{-}$</b>→ Dimagnetic <br>
On the basis of this <br>
<b>$K_{2}MnO_{4}$</b>→ Paramagnetic <br>
<b>$KMnO_{4}$</b>→ Dimagnetic <br>
<b>BUT </b><br>
According to my class teacher <br>
<b>$KMnO_{4}$</b>→ Paramagnetic <br>
<b>Conf... |
According to me <br>
$\ce{MnO4^2-}$→ Paramagnetic <br>
$\ce{MnO4^-}$</b>→ Diamagnetic <br>
On the basis of this <br>
$\ce{K2MnO4}$→ Paramagnetic <br>
$\ce{KMnO4}$→ Diamagnetic <br>
<b>BUT </b><br>
According to my class teacher <br>
$\ce{KMnO4}$→ Paramagnetic <br>
<b>Confusion :-</b> $\ce{KMnO4}$ ... |
I'm trying to get a sense of how cu2+ and nh3 are bonded together because it doesn't make any!
I understand that nh3 has a lone pair of electrons that can be donated (right?), but since there are four molecules of nh3, then there are 4 pairs, and cu2+ only needs two!
the reaction in my textbook was written like this... |
How Cu(NH3)4 is formed? |
I'm trying to get a sense of how $\ce{Cu^2+}$ and $\ce{NH3}$ are bonded together because it doesn't make any!
I understand that $\ce{NH3}$ has a lone pair of electrons that can be donated (right?), but since there are four molecules of $\ce{NH3}$, then there are 4 pairs, and $\ce{Cu^2+}$ only needs two!
the reaction... |
How Cu(NH3)4^2+ is formed? |
When we do nitrosation of phenols, we get para-nitrosophenol as the major product, which tautomerises to quinone monoxime. [This](https://pubs.acs.org/doi/10.1021/ja01318a062) article states that it largely exists in the quinonoid form.
My question is, why? I know that nitroso form is less stable than the oxime for... |
Why is quinone monoxime more stable than para nitrosophenol? |
When we do nitrosation of phenols, we get para-nitrosophenol as the major product, which tautomerises to quinone mono oxime. [This](https://pubs.acs.org/doi/10.1021/ja01318a062) article states that it largely exists in the quinonoid form.
My question is, why? I know that nitroso form is less stable than the oxime f... |
Why is quinone mono oxime more stable than para nitrosophenol? |
[Gluten][1] describes a subset of proteins (glutenins and gliadins) found in wheat grain and making up a large fraction of the protein found in common wheat flour (>70%). Since the protein fraction of wheat flour can represent >10%/wt, the gluten fraction commonly represents >5%/wt of the flour.
Given the requiremen... |
So I understand that there exists the shrodinger's equation, which on solving,gives the wave function of an electron. The wave function as I understand, gives all possible information about an electron(any extra information on wavefunction will be appreciated).
Could someone actually solve a shrodinger's equation fo... |
Which electrons are in HOMO in a peptide bond? |
[Gluten][1] describes a subset of proteins (glutenins and gliadins) found in wheat grain and making up a large fraction of the protein found in common wheat flour (>70%). Since the protein fraction of wheat flour can represent >10%/wt, the gluten fraction commonly represents >5%/wt of the flour.
Given the requiremen... |
[Gluten][1] describes a subset of proteins (glutenins and gliadins) found in wheat grain and making up a large fraction of the protein found in common wheat flour (>70%). Since the protein fraction of wheat flour can represent >10%/wt, the gluten fraction commonly represents >5%/wt of the flour.
Given the requiremen... |
[Gluten][1] describes a subset of proteins (glutenins and gliadins) found in wheat grain and making up a large fraction of the protein found in common wheat flour (>70%). Since the protein fraction of wheat flour can represent >10%/wt, the gluten fraction commonly represents >5%/wt of the flour.
Given the requiremen... |
[Gluten][1] describes a subset of proteins (glutenins and gliadins) found in wheat grain and making up a large fraction of the protein found in common wheat flour (>70%). Since the protein fraction of wheat flour can represent >10%/wt, the gluten fraction commonly represents >5%/wt of the flour.
Given the requiremen... |
@jakebeal's [excellent answer](https://biology.stackexchange.com/a/98349/27918) to *Why do animal cells “mistake” rubidium ions for potassium ions?* includes the following passage:
>In the case of potassium versus sodium, which are both very important in biochemistry, a recently discovered mechanism in sodium-potass... |
Help understanding how "steric effects" are distinct from "electronic effects"? |
When we do nitrosation of phenols, we get para-nitrosophenol as the major product, which tautomerises to quinone mono oxime. [This](https://pubs.acs.org/doi/10.1021/ja01318a062) article states that it largely exists in the quinonoid form.
My question is, why? I know that nitroso form is less stable than the oxime f... |
When we do nitrosation of phenols, we get para-nitrosophenol as the major product, which tautomerises to quinone mono oxime. [This](https://pubs.acs.org/doi/10.1021/ja01318a062) article states that it largely exists in the quinonoid form.
My question is, why? I know that nitroso form is less stable than the oxime f... |
Variety is the spice of life. I have made an organic compound myself. Can you please tell me the name?
 |
What is the IUPAC name of this organic compound? |
Variety is the spice of life. I have made an organic compound myself. Can you please tell me the name?
 |
Variety is the spice of life. I have made an organic compound myself. Can you please tell me the name?
I thought that the correct answer is -
**3,3-dibromo-2,4-dichloro-1,4-difluoro-2,4-diiodo-1-methylbutan-1-ol**
, because the haloalkane group is to be given in the alphabetical order and the alcohol group is the do... |
Variety is the spice of life. I have made an organic compound myself. Can you please tell me the name?
I thought that the correct answer is -
**3,3-dibromo-2,4-dichloro-1,4-difluoro-2,4-diiodo-1-methylbutan-1-ol**, because the haloalkane group is to be given in the alphabetical order and the priority of the alcohol g... |
How tetraamminecopper(II) is formed? |
Let me tell what I understand of the concepts on which the question is based first.
Heat is a flow of energy that takes place due to a temperature gradient.
When doing reversible isothermal expansion of an ideal gas, even though there is no net change in the system's temperature before and after the process, ea... |
My teacher said, "Rutherford thought that all the Alpha particles would directly go through the gold foil without any collision if the plum pudding model was right. Because, as said in plum pudding model, positive charges are arranged in a balanced way in the atom with electrons like plum in pudding. As there is no den... |
There are many ways to describe chemical bonds. Copper II ion binds to some anions with ionic bonds in solids, sometimes in covalent bonds (Ref 1).
In aqueous solution, copper II ions are surrounded (hydrated) with six water molecules, with the oxygen ends pointing in, toward the positive copper ion. Water is acting... |
We know that if the dative bond is directed towards less electronegative element, it is ignored while calculating the oxidations state and it is considered as +2 for donor and -2 for the recipient when it is directed towards the more electronegative species. But in the case of the same electronegative species, Why the ... |
In dative bond S→ S, why are the Oxidation state of donor S = +2 and recipient S= -2 although both of them have the same electronegativity? |
For harmonic oscillator with quantum number n, what range of x coordinate is allowed classically? [Tried to use the fact that potential energy is negative. Does it have something to do with Bohr's Correspondence Principle? I also tried using the fact that potential energy will be negative]
|
I am told that the area under the PV curve gives the magnitude of work done by a gas.
Let $V_i$ be the initial volume, $V_f$ be the final volume, and the pressure as a function of volume be given by $P=f(V)$. To my understanding, the work done is given by the area bounded by $x=V_i$, $x=V_f$, $P=F(v)$ and $y=0$.
... |
For harmonic oscillator with quantum number n, what range of x coordinate is allowed classically? [ Does it have something to do with Bohr's Correspondence Principle? ]
|
Calculate the cell potential for the voltaic cell that results when the following two half-cells are
connected at 25°C:
(1) a platinum electrode inserted into a solution of 0.10 M Co3+ and 0.0010 M Co2+
(2) a copper electrode inserted into a solution of 0.010 M Cu2+ ions
>Answer. 1.66 V
how it's calculated... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are
connected at 25°C:
(1) a platinum electrode inserted into a solution of 0.10 M Co3+ and 0.0010 M Co2+
(2) a copper electrode inserted into a solution of 0.010 M Cu2+ ions
>Answer. 1.66 V
how it's calculated... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
In a quantum harmonic oscillator that is in the state with quantum number $n$, what range of the position $x$ is allowed classically? Does it have something to do with Bohr's correspondence principle?
|
The order of ionic radii for halides and hydride is apparently as follows:
$$\ce{F-} < \ce{Cl-} < \ce{Br-} < \ce{H-} < \ce{I-}$$
Why is the hydride ion so large, even larger than bromide which has filled 3d and 4p subshells? Some claim that it is because the ratio of positive to negative charge is 0.5, which is ... |
Why is the ionic radius of hydride so large? |
I am currently running a project to detect chloride level in crude palm oil. On most lab service websites, some offer total chloride detection and others offer organic chloride detection. What are the differences between total chloride and organic chloride? |
This question is based on [@Heisenberg's Question](https://chemistry.stackexchange.com/questions/9679/why-does-having-equivalent-resonance-structures-give-more-stability) with the same title.
I recently offered a bounty for a more detailed answer for the same question.
These are the things I would like to be in the... |
Why does having equivalent resonance structures give more stability (Related)? |
As porphyrin and Buck Thorn nicely explained, once you establish that $K_p$ is independent of pressure then, assuming an ideal system, it necessarily follows that $K_c$ is indepedent of pressure as well.
But I'd like to take a closer look at the pressure-independence of $K_p$. The reason $K_p$ is pressure-independ... |
As porphyrin and Buck Thorn nicely explained, once you establish that $K_p$ is independent of pressure then, assuming an ideal system, it necessarily follows that $K_c$ is indepedent of pressure as well.
But I'd like to take a closer look at the pressure-independence of $K_p$. The reason $K_p$ is pressure-independ... |
In the resonance of $CH_2^--CH=CH_2$, the only other structure is $CH_2=CH-CH_2^-$. Why isn't there a resonating structure $CH_2^+-CH^--CH_2^-$? What's the criteria for bonds localising as lone pairs? |
Why aren't these considered as different resonating structures? |
Why is quinone mono oxime more stable than 4-nitrosophenol? |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
Calculate the cell potential for the voltaic cell that results when the following two half-cells are connected at $\pu{25 ^\circ C}$:
(1) A platinum electrode inserted into a solution of $\pu{0.10 M}$ $\ce{Co^3+}$ and $\pu{0.0010 M}$ $\ce{Co^2+}$
(2) A copper electrode inserted into a solution of $\pu{0.010 M}$ $... |
I am wondering why $\ce{[Fe(CN)6]^4-}$ is colored and at the same time diamagnetic. For a transition metal to be diamagnetic all the electrons should be paired up in the d orbitals and at the same time a transition metal is colored because certain wavelength of a white light is absorbed during the electron movement to ... |
Why is hexacyanoferrate(II) colored and at the same time diamagnetic? |
There are only two resonance structures of allyl anion with negative charge distributed over positions 1 and 3:
$$\ce{\overset{-}{C}H2-CH=CH2 <-> CH_2=CH-\overset{-}{C}H2}.$$
What's the criteria for bonds localizing as lone pairs? Why isn't there a third resonance structure
$$\ce{\overset{+}{C}H2-\overset{-}{C... |
Why does allyl anion have only two resonance structures? |
I understand that more heat energy= higher rate of electrolysis, but can someone explain using higher-level terms why this occurs and if there are any theories or rules that explain this? |
Why does higher temperature affect the rate of electrolysis? |
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