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My textbook frequently mentions:
$sp^3$ hybrid orbital has 25% $s$-character and 75% $p$-character.
My questions are: what are these "character"? And how these characters influence the bond and the hybrid orbital? |
I'm working on a project (school level) and in it I'll be dealing with the pressure generated by water when superheated.
I could understand the concept of superheated water but superheated steam is hard to understand. Are both inter-related, i mean that when water is superheated then it changes into superheated ste... |
Difference between Superheated steam and Superheated water? |
My textbook frequently mentions:
> $\mathrm{sp^3}$ hybrid orbital has 25% $\mathrm{s}$-character and 75% $\mathrm{p}$-character.
My questions are: What are these "character"? And how do these characters influence the bond and the hybrid orbital? |
What does it mean when it is said, that a sp³ orbital has 25% s character? |
Are these 2 molecular structures of ammonium bicarbonate the same?
http://upload.wikimedia.org/wikipedia/commons/6/65/Ammonium_bicarbonate.PNG
http://www.mpbio.com/images/product-images/molecular-structure/02150107.png
|
Are these 2 molecular structures of ammonium bicarbonate the same? |
Are these 2 molecular structures of ammonium bicarbonate the same?
![http://upload.wikimedia.org/wikipedia/commons/6/65/Ammonium_bicarbonate.PNG][1]
![http://www.mpbio.com/images/product-images/molecular-structure/02150107.png][2]
[1]: https://i.stack.imgur.com/0BrZL.png
[2]: https://i.stack.imgur.com/a... |
Are these 2 molecular structures of ammonium bicarbonate the same?
A:
![http://upload.wikimedia.org/wikipedia/commons/6/65/Ammonium_bicarbonate.PNG][1]
B:
![http://www.mpbio.com/images/product-images/molecular-structure/02150107.png][2]
[1]: https://i.stack.imgur.com/0BrZL.png
[2]: https://i.st... |
I believe your reasoning is correct (more or less). Solvation is influenced by charge to size ratios. Higher the charge to size ratio, the easier it is for the species to be solvated by water molecules.
Apply this idea to both your cases. (note: in the second case, I don't get your argument about molar mass. The ... |
What happens if I make a hole in a container with superheated water? |
Are these 2 molecular structures of ammonium bicarbonate the same?
A:
![http://upload.wikimedia.org/wikipedia/commons/6/65/Ammonium_bicarbonate.PNG][1]
B:
![http://www.mpbio.com/images/product-images/molecular-structure/02150107.png][2]
[1]: https://i.stack.imgur.com/0BrZL.png
[2]: https://i.st... |
Are these 3 molecular structures of ammonium bicarbonate the same?
A:
![http://upload.wikimedia.org/wikipedia/commons/6/65/Ammonium_bicarbonate.PNG][1]
B:
![http://www.mpbio.com/images/product-images/molecular-structure/02150107.png][2]
[1]: https://i.stack.imgur.com/0BrZL.png
[2]: https://i.st... |
Are these 3 molecular structures of ammonium bicarbonate the same? |
Will a reaction(E2) that has 2 potential product go faster than a reaction that has 3 potential products?
**specific information** - the molecules in the pictures are each reacting with methanol. I figured it's an E2 reaction (I hope I'm right) and the question is which one will go faster?
![cyclohexylbromides][2]... |
Are these 3 molecular structures of ammonium bicarbonate the same?
A:
![http://upload.wikimedia.org/wikipedia/commons/6/65/Ammonium_bicarbonate.PNG][1]
B:
![http://www.mpbio.com/images/product-images/molecular-structure/02150107.png][2]
C:
![http://www.caslab.com/Chemical-Search/Chemical-Structur... |
I am currently in the process of studying enzyme catalysis and am struggling to get to grips with this concept. As far as I understand, the propinquity effect allows substrates to bind with enzymes in the conformation which would facilitate the reaction, thus increasing the reaction rate. Could someone expand on the wh... |
What is the pH of a solution of $3.4 \times 10^{-10}$ moles of $\ce{HCl}$ in a volume of $150.7L$?
This is dilute so I expect pH to be high.
$\frac{3.4 \times 10^{-10} mol}{150.7L} = 2.26 \times 10^{-12} \frac{mol}{L} $
Then pH is 11.65. Is this correct? |
As the electronic configuration of gold is [Kr] $4d^{10} 4f^{14} 5s^2 5p^6 5d^{10} 6s^1$, the valence shell is not completely full. Why gold is not corroded? |
Why gold is not corroded? |
As the electronic configuration of gold is [Kr] $4d^{10} 4f^{14} 5s^2 5p^6 5d^{10} 6s^1$, the valence shell is not completely full. Why doesn't gold corrode? |
Why doesn't gold corrode? |
Chapter 14 of Harris' Quantitative Chemical Analysis has a helpful section entitled, *an intuitive way to think about cell potentials.* Here's the corresponding graphic:
![enter image description here][1]
In this case, the author is describing a Galvanic cell with cadmium as the anode and silver as the cathode.... |
The Gattermann-Koch Reation involves the formation of an aryl aldehyde using carbon monoxide and hydrochloric acid as reactants. The reaction is catalyzed by Aluminum Tri-Chloride in the presence of trace amounts of Cuprous Chloride.
![enter image description here][1]
What I don't understand about this reaction is th... |
How is it possible to distinguish antimony from lead? |
How will the 129 Xe NMR of XeOF4 look like?
I know that its electron pair geometry is octahedral, and the molecular pair geometry is square pyrimidal.
I believe that the lone pair on Xe will take the axial position (less sterically crowded) and the oxygen will lie in the same plane as the 3 equatorial fluorines,... |
How will the 129 Xe NMR of XeOF4 look like?
I know that its electron pair geometry is octahedral, and the molecular pair geometry is square pyrimidal.
I believe that the lone pair on Xe will take the equatorial position (less sterically crowded), alongside the oxygen and 2 other equatorial fluorines in the same ... |
Can someone explain to me why the I-Cl bond length in ICl2- (charge of -1) is longer than in ICl2+ (charge of +1) ?
Here are a few explanations that I have in mind. Please advise the veracity of my arguments:
1. I in ICl2- :sp3d hybridized. I in Icl+ : sp3 hybridized. Since additional promotion energy is required... |
There are a couple of reasons why Mercury is a liquid at STP, I will go through each of them with an explanation that won't be too complex for your understanding.
**First of all understanding why most metals are metallic is a good place to start.** This happens because of the sharing of valence electrons. The sharin... |
The $\ce{^{129}Xe}$ nmr spectrum of $\ce{XeOF4}$ is a sharp, **quintuplet** of peaks ([reference][1], p. 445). As you note, $\ce{XeOF4}$ adopts a square pyramidal geometry ([reference][2]), but the lone pair occupies an axial position.
![enter image description here][3]
Therefore, the 4 equatorial fluorines are ... |
My textbook frequently mentions:
> $\mathrm{sp^3}$ hybrid orbital has 25% $\mathrm{s}$-character and 75% $\mathrm{p}$-character.
What are these "characters"? And how do these characters influence the bond and the hybrid orbital?
|
What does it mean when it is said that an sp³ orbital has 25% s character? |
Can someone explain to me why the $\ce{I-Cl}$ bond length in $\ce{ICl2-}$ (charge of -1) is longer than in $\ce{ICl2+}$ (charge of +1) ?
Here are a few explanations that I have in mind. Please advise the veracity of my arguments:
1. I in $\ce{ICl2-}$ :$sp^3d$ hybridized. $\ce{I}$ in $\ce{ICl+}$ : $sp^3$ hybridize... |
How will the $\ce{^129Xe}$ NMR of $\ce{XeOF4}$ look like?
I know that its electron pair geometry is octahedral, and the molecular pair geometry is square pyrimidal.
I believe that the lone pair on $\ce{Xe}$ will take the equatorial position (less sterically crowded), alongside the oxygen and 2 other equatorial f... |
Why is the $\ce{I-Cl}$ bond length in $\ce{ICl2-}$ (charge of -1) is longer than in $\ce{ICl2+}$ (charge of +1) ?
Here are a few explanations that I have in mind. Please critique.
1. I in $\ce{ICl2-}$ is $sp^3d$ hybridized. $\ce{I}$ in $\ce{ICl+}$ is $sp^3$ hybridized. Since additional promotion energy is require... |
What will the $\ce{^129Xe}$ NMR spectrum of $\ce{XeOF4}$ look like?
I know that its electron pair geometry is octahedral, and the molecular pair geometry is square pyrimidal.
I believe that the lone pair on $\ce{Xe}$ will take the equatorial position (less sterically crowded), alongside the oxygen and 2 other eq... |
The $\ce{^{129}Xe}$ nmr spectrum of $\ce{XeOF4}$ is a sharp, **quintuplet** of peaks ([reference][1], p. 445). As you note, $\ce{XeOF4}$ adopts a square pyramidal geometry ([reference][2]), but the lone pair occupies an axial position.
![enter image description here][3]
Therefore, the 4 equatorial fluorines are ... |
The boiling point of ammonia is −33 °C while that of $\ce{HCN}$ is 25 °C. In a recent AP Chemistry test, a free response question asked why this is the case. Can someone shine light on this?
EDIT:
Based on Jan's answer:
1. Although the $\ce{C-H}$ bond does not usually exhibit good hydrogen bond, $\ce{H-CN}... |
What will the $\ce{^129Xe}$ NMR spectrum of $\ce{XeOF4}$ look like?
I know that its electron pair geometry is octahedral, and the molecular pair geometry is square pyramidal.
I believe that the lone pair on $\ce{Xe}$ will take the equatorial position (less sterically crowded), alongside the oxygen and 2 other eq... |
What does the 129Xe NMR spectrum of XeOF4 look like? |
I'm making a solution with linear polyethylene. The bottle indicates that the substance is hygroscopic and must be dealt with under inert gas. Is this really necessary? I don't currently have access to such a space - just me, the PEI and a balance. Somebody who has worked with the polyelectrolyte, do help me! |
In the multistage synthesis of 4-bromobenzenamine, why must the solution be rendered alkaline prior to the steam distillation after the hydrolysis of 4-bromo-N-ethanoylbenzenamine? |
The boiling point of ammonia is −33 °C while that of $\ce{HCN}$ is 25 °C. In a recent AP Chemistry test, a free response question asked why this is the case. Can someone shine light on this?
Based on Jan's answer:
1. Although the $\ce{C-H}$ bond does not usually exhibit good hydrogen bond, $\ce{H-CN}$ is a sp... |
Why does HCN boil at a higher temperature than NH3? |
When I start studying electrochemistry,I learn the words molten and aqueous. I don't have a problem for aqueous but I'm a little bit confuse about molten.
For me, molten means melt, which means become liquid from solid. But why we say molten lead (II) bromide instead of liquid lead (II) bromide?
I mean both are sam... |
Considering the Metabolic Pathway:
http://www.genome.jp/kegg-bin/show_module?M00166
Consider the reaction R01523(the very first reaction). How is it possible to know that the compound C00199(D-Ribulose 5-phosphate) will get transformed to C01182(D-Ribulose 1,5-bisphosphate)? What are the factors on which this tran... |
Considering the Metabolic Pathway:
http://www.genome.jp/kegg-bin/show_module?M00166
Consider the reaction R01523(the very first reaction). How is it possible to know that the compound C00199(D-Ribulose 5-phosphate) will get transformed to C01182(D-Ribulose 1,5-bisphosphate)? <br><br>What are the factors on which t... |
Hybridisation is a purely mathematical concept, which makes it possible to explain experimentally found structures. The most prominent example for this is methane, where you can consider the central carbon atom to be $\mathrm{sp^3}$ hybridised. Formally, the $\mathrm{s}$ orbital and the three $\mathrm{p}$ orbitals can ... |
Probably you are having problems with Le Chatelier's Principle.
Suppose you have an equilibrium established between four substances $\ce{A}$, $\ce{B}$, $\ce{C}$ and $\ce{D}$.
<br>
> What would happen if you changed the conditions by increasing the
> concentration of $\ce{A}$?
<br>
According to Le Chatelier,... |
Why are neutron scattering factors essentially independent of $2\theta$, whereas X-ray scattering factors drop off with increasing $2\theta$ ? |
Problem:
---
>A buffer was made by mixing 500 mL of 1 M (mol/L) acetic acid and 500 mL of 0.5 M calcium acetate.
>What are the resulting concentrations of acetic acid (henceforth called $\ce{AcH}$), $\ce{Ca^2+}$ and acetate (henceforth called $\ce{Ac- }$, and what is the resulting pH? $K_\text{a}$(acetic acid) = ... |
How to calculate the pH of an acetic acid/ calcium acetate buffer? |
I understand the concept of incomplete combustion and that it occurs when oxygen is not a large enough supply to allow for complete combustion. My question is: how can we model combustion properly in terms of predicting the ratio of complete to incomplete combustion? Is it possible to use basic kinetic with reaction ra... |
Predicting incomplete combustion? |
After looking at the website I found the reaction is based off of an enzyme called: [phosphoribulokinase][1]. In biological systems many reactions occur under the auspice of enzymes or proteins. These are incredibly large molecules made of an extremely long chain of amino acids which are a set of 26 or so small molecul... |
I'm making a solution with linear [poly(ethyleneimine)](http://en.wikipedia.org/wiki/Polyethylenimine) $\ce{[CH2CH2NH]_{n}}$. The bottle indicates that the substance is hygroscopic and must be dealt with under inert gas. Is this really necessary? I don't currently have access to such a space - just me, the PEI and a... |
We know that the electron configuration in 3d orbitals of Zn2+, in 4d orbitals of Hg2+ & in 5d orbitals of Cd2+ ions are completely same.
Then why the compounds of Hg(II) & Cd,such as HgO,CdS radiate versatile colour where ZnO,ZnS are white?
|
why HgO & CdS compounds are colourful? |
We know that the electron configuration in 3d orbitals of Zn<sup>2+</sup>, in 4d orbitals of Hg<sup>2+</sup> & in 5d orbitals of Cd<sup>2+</sup> ions are completely same.
Then why the compounds of Hg(II) & Cd, such as HgO, CdS radiate versatile colour where ZnO, ZnS are white?
|
We know that the electron configuration in 3d orbitals of Zn<sup>2+</sup>, in 4d orbitals of Cd<sup>2+</sup> & in 5d orbitals of Hg<sup>2+</sup> ions are completely same.
Then why the compounds of Hg(II) & Cd, such as HgO, CdS radiate versatile colour where ZnO, ZnS are white?
|
Is there a way of comparing which salt is more soluble without knowing their $ K_{sp}$ data or performing experiments?
For example, comparing $\ce{Hg2Cl2}$ and $\ce{Cr2(SO4)3}$.
I am not sure but can I compare lattice and hydration energy relatively or the ion size and estimate?
Experiments will ... |
How do I predict the solubility of a compound in a mixture of water and an organic co-solvent? |
Does anyone know if I cool a liquid crystal with a deformed nematic phase quickly it will preserve the deformation in the crystal lattice? I didn't never see that in classical books on liquid crystals. |
Is there a way to detect whether sugar is completely dissolved in a cup of water other than looking at the bottom of the cup? |
According to the Nernst equation, the electrode potential $E$ is
$$E = E^\circ - \frac{RT}{nF}\ln\frac{[\ce{M}]}{[\ce{M^{$n$+}}]}$$
Question is, why? Assuming a simple galvanic cell, we know that in general if the temperature is increased, there should be more collisions of the solution with the electrode, resultin... |
Why does an increase in temperature decrease the electrode potential? |
Is there a way to detect whether sugar is completely dissolved in a cup of water other than looking at the bottom of the cup?
I was wondering if there is a test or something that can be carried out to determine whether sugar is fully dissolved. Thanks! |
Is there a way to detect whether sugar is completely dissolved in a cup of water other than looking at the bottom of the cup?
I was wondering if there is a test or something that can be carried out to determine whether sugar is fully dissolved. |
Does anyone know if I were to cool a liquid crystal with a deformed nematic phase quickly, if it will preserve the deformation in the crystal lattice?
I didn't find any information in classical books on liquid crystals. |
Choose:
$$\ce{Energy + 2KClO3 (s) <=> 2KCl(s) + 3O2 (g)}$$
The reaction will be more active in the reverse direction if:
1) $\ce{O_2}$ is added
2) more $\ce{KCl}$ salt is added.
3) More $\ce{KClO3}$ is added
4) Increasing the temperature.
My thoughts :
I think (1) and (2) are both right. But t... |
We know that the electron configuration in $3d$ orbitals of $\ce{Zn^2+}$, in $4d$ orbitals of $\ce{Cd^2+}$ and in $5d$ orbitals of $\ce{Hg^2+}$ ions are completely same.
Then why the compounds of $\ce{Hg(II)}$ and $\ce{Cd}$, such as $\ce{HgO}$, $\ce{CdS}$ radiate versatile colour where $\ce{ZnO}$, $\ce{ZnS}$ are whi... |
Choose:
$$\ce{Energy + 2KClO3 (s) <=> 2KCl(s) + 3O2 (g)}$$
The reaction will be more active in the reverse direction if:
1) $\ce{O_2}$ is added
2) more $\ce{KCl}$ salt is added.
3) More $\ce{KClO3}$ is added
4) Increasing the temperature.
My thoughts :
I think (1) and (2) are both right. But t... |
I have had two types of urea fertiliser analysed, the results are as follows:
$\ce{46N}$ (46% nitrogen) - which is sold as a urea fertiliser, tests at 46.1% ureic nitrogen.
$\ce{38N}$ $\ce{19S}$ (38% nitrogen, 19% sulphur) - which I understand to contain ammonium sulphate and urea, tests at 33% nitric nitrogen an... |
Choose:
$$\ce{Energy + 2KClO3 (s) <=> 2KCl(s) + 3O2 (g)}$$
The reaction will be more active in the reverse direction if:
1) $\ce{O_2}$ is added
2) more $\ce{KCl}$ salt is added.
3) More $\ce{KClO3}$ is added
4) Increasing the temperature.
My thoughts :
I think (1) and (2) are both right. But t... |
Choose:
$$\ce{Energy + 2KClO3 (s) <=> 2KCl(s) + 3O2 (g)}$$
The reaction will be more active in the reverse direction if:
1) $\ce{O_2}$ is added
2) more $\ce{KCl}$ salt is added.
3) More $\ce{KClO3}$ is added
4) Increasing the temperature.
My thoughts :
I think (1) and (2) are both right. But t... |
There are two simple ways to calculate charges on atoms in molecules which can be done by hand.
The first relies on the concept of *oxidation numbers*. To define these, take a target molecule/ion and *break all covalent bonds by transferring both electrons in the bond to the more electronegative atom* (usually based... |
There are two simple ways to calculate charges on atoms which can be done by hand.
The first relies on the concept of *oxidation numbers*. To define these, take a target molecule/ion and *break all covalent bonds by transferring both electrons in the bond to the more electronegative atom* (usually based on the Pauli... |
*Ok so this is the proposed mechanism for the Wittig Reaction as stated by my textbook LG Wade. I have some doubts regarding this mechanism:*
![enter image description here][1]
![enter image description here][2]
> 1)Why is only Triphenyl phosphine used here.Why not some stronger
> nucleophile like say... |
There are two simple ways to calculate charges on atoms which can be done by hand.
The first relies on the concept of *oxidation numbers*. To define these, draw the Lewis structure of a target molecule/ion and *break all covalent bonds by transferring both electrons in the bond to the more electronegative atom* (usu... |
This is the [Wikipedia][1] image for the reaction mechanism:
![diekmann reaction][2]
In the final protonation step, why does the enol tautomerizes to the keto form?
The double bond is in resonance with the ester's carbonyl double bond. Also the enol's -OH group would form H-bond.
Shouldn't th... |
This is the [Wikipedia][1] image for the reaction mechanism:
![diekmann reaction][2]
In the final protonation step, why does the enol tautomerizes to the keto form?
The double bond is in resonance with the ester's carbonyl double bond. Also the enol's -OH group would form H-bond.
Shouldn't en... |
The low energy portion (the part dealing with the $\ce{2s}$ and $\ce{2p}$ electrons) of the photoelectron (PE) spectrum of methane is reproduced below.
![enter image description here][1]
([image source][2])
The reaction being examined is
$$\ce{CH4 + ~energy -> [CH4]^{+} + ~e^-}$$
The fact that 2 peaks in r... |
The low energy portion (the part dealing with the $\ce{2s}$ and $\ce{2p}$ electrons) of the photoelectron (PE) spectrum of methane is reproduced below.
![enter image description here][1]
([image source][2])
The reaction being examined is
$$\ce{CH4 + ~energy -> [CH4]^{+} + ~e^-}$$
The fact that 2 peaks in r... |
> why does the enol tautomerizes to the keto form?
In systems like this we wouldn't expect the enol to predominate. The keto-enol interconversion is an equilibrium and will be guided by **thermodynamic** factors. Let's take a look.
A carbonyl double bond has a bond strength around 178 kcal/mol. A carbon-carbon... |
Since formaldehyde gas is flammable, is there a safe way to burn it, and can this be done to dispose of the gas or neutralize its harmful effects (tear production, respiratory problems, etc.)? |
Burning formaldehyde gas: can this be done for disposal? |
This is the [Wikipedia][1] image for the reaction mechanism:
![diekmann reaction][2]
In the final protonation step, why does the enol tautomerize to the keto form?
In the enol form the carbon-carbon double bond is in resonance with the ester's carbonyl double bond. Also the enol's $\ce{-OH}$ group wo... |
Since formaldehyde gas is flammable, is there a safe way to burn it, and can this be done to dispose of the gas or neutralize its harmful effects (tear production, respiratory problems, etc.)?
This is a more detailed form of my earlier question, including the context of "gas disposal". |
How to simulate surface tension? |
Suppose I have a photochemical reaction in gas phase, such as
$$
\ce{CO2 + {$h\nu$} -> CO + O}.
$$
I would like to work through the thermodynamics of such a reaction and understand the meaning of every term.
For a non-photochemical reaction, such as $\ce{CO + O -> CO2}$, I have a good understanding of how the ch... |
A galvanic cell consists of a standard hydrogen electrode and a copper electrode.
2 H+ (aq) → H2 (g) EO = 0.00 V
Cu2+ (aq) + 2e- → Cu (s) EO = 0.34 V
Suppose the copper electrode is placed in a solution of unknown copper (II) concentration. The cell potential is measured to be 0.195 V. Determ... |
![enter image description here][1]
In IUPAC naming double bonds take preference over an alkane chain of any length, right? So the above should be named as `2-ethylnon-1-ene`.
However, when I verify with chemdraw it gives the answer as `3-methylenedecane`. I cannot seem to find any mention of double bond side chai... |
In which cases clemmenson reduction is preferred over Wolff kishner reduction?
One thing is that clemmenson reduction is done under acidic condition whereas Wolff Kishner is done under basic condition, and that I think decides somewhat which to choose depending of the nature and other groups present in the reactant. B... |
In which cases is the Clemmensen reduction is preferred over the Wolff-Kishner reduction?
One thing is that the Clemmensen reduction is done under acidic conditions whereas the Wolff-Kishner reaction is done under basic condition, and that I think decides somewhat which to choose depending of the nature and other ... |
This question goes along the line of [what does it mean when it is said that an sp3 orbital has 25% s-character][1]. It also intrigued me so I have tried to find answer, which would not break my hybridised orbital view.
What you clearly see from the spectrum is that there are two bands, corresponding to different en... |
![The couplings to be done are 1 and 2. A is the starting reactant and B is the product I want.][1]
[1]: https://i.stack.imgur.com/wzun6.jpg
A is the reactant and b is the product. There are two couplings to be done. 1 and 2. Which sequence should be followed, ie. 1 should be coupled first or 2 should be couple... |
According to IUPAC rules first think you need to see is **longest carbon chain** which is 10(deca) over here.
Then while **numbering the Carbon** double bond is given preference.
So above compound is 10 carbon chain in which 3rd carbon is double bonded.
Thus, **3-methylenedecane** is correct name.
****
... |
The boiling point of ammonia is −33 °C while that of $\ce{HCN}$ is 25 °C. In a recent AP (Advanced Placement) Chemistry test, a free response question asked why this is the case. Can someone shine light on this?
Other information on AP test: it is a test for high school students in the U.S. to earn credits for a colle... |
According to IUPAC rules first thing you need to see is **longest carbon chain** which is 10(deca) over here.
Then while **numbering the Carbon** double bond is given preference.
So above compound is 10 carbon chain in which 3rd carbon is double bonded.
Thus, **3-methylenedecane** is correct name.
****
... |
According to IUPAC rules first thing you need to see is **longest carbon chain** which is 10(deca) over here.
Then while **numbering the Carbon** double bond is given preference.
So above compound is 10 carbon chain in which 3rd carbon is double bonded.
Thus, **3-methylenedecane** is correct name.
****
... |
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