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What is the origin of the Quadratic factor in calculation of XRD peaks? |
*The kinetic theory assumes that, for an ideal gas, the volume taken up by the molecules themselves is entirely negligible compared with the volume of the container. For a real gas, that assumption isn't true. The molecules themselves do take up a proportion of the space in the container. The space in the container... |
*The kinetic theory assumes that, for an ideal gas, the volume taken up by the molecules themselves is entirely negligible compared with the volume of the container. For a real gas, that assumption isn't true. The molecules themselves do take up a proportion of the space in the container. The space in the container ava... |
Can anyone propose a mechanism for Method A from [this paper][1]? Almost all other sources online use method B.
[![enter image description here][2]][2]
[1]: http://orgsyn.org/Content/pdfs/procedures/CV4P0898.pdf
[2]: https://i.stack.imgur.com/zbka7.png |
Can anyone propose/draw a mechanism for Method A, below, from [this paper][1]? Almost all other online sources use method B and reagents such as SOCl3.
[![enter image description here][2]][2]
[1]: http://orgsyn.org/Content/pdfs/procedures/CV4P0898.pdf
[2]: https://i.stack.imgur.com/zbka7.png |
> When the $\mathrm{pH}$ was $5.0$, the temperature was $\pu{25 °C}$,the $K_\mathrm{D}$ was $\pu{5 μM}$, and [L] was equal to $K_D$, the protein(s) were half bound.
Question considers half bound condition where $[L]= _$
>If $K_\mathrm{D} = \pu{20 μM}$ and $\mathrm{pH} = 6.5$, what is the impact on binding affin... |
Consider a balloon filled with a gas. The volume we mean is the volume of the balloon, whatever is inside. The perfect gas hypothesis will change the properties of a gas. For example, for the same balloon, we would expect a real gas to exert a stronger pressure outward than a perfect gas, since it has less space to mov... |
Can anyone propose/draw a mechanism for Method A, below, from [this paper][1]? Almost all other literature use method B and reagents such as SOCl3.
[![enter image description here][2]][2]
[1]: http://orgsyn.org/Content/pdfs/procedures/CV4P0898.pdf
[2]: https://i.stack.imgur.com/zbka7.png |
### In defence of Kekulé structures
The real answer is, in my view, much more nuanced than ron's answer would have one believe. I sincerely think it is too simplistic to just say that it is "wrong".
To understand what I mean, we need to look at the concept of a resonance hybrid, which is a weighted average of sev... |
Can anyone propose/draw a mechanism for Method A, below, from [this paper][1]? Almost all other literature use method B and reagents such as SOCl2.
[![enter image description here][2]][2]
[1]: http://orgsyn.org/Content/pdfs/procedures/CV4P0898.pdf
[2]: https://i.stack.imgur.com/zbka7.png |
The reaction of benzene and γ-butyrolactone with AlCl<sub>3</sub> was investigated by [Truce and Olson<sup>1][1]</sup> in 1952. The authors found that the ratio of γ-phenylbutyric acid to α-tetralone was dependent on the AlCl<sub>3</sub>/lactone ratio. The larger the ratio; the more α-tetralone... |
So this morning I purchased a coffee. As a not uncommon event the lid on the coffee cup didn't have a hole completely punched through (a gas inflow hole). This makes it difficult to drink the coffee because I'm essentially creating a vacuum when I suck out the coffee.
I was wondering then. Is it atmospheric pressure... |
A combination of gravity and the suction you apply with your lips ("suck") help empty the cup, assuming as you do that the coffee in the cup leaves a vacuum as it exits. This is similar to the "problem" of emptying a bottle of liquid when you invert it (the mouth facing downward). The challenge is most evident with hon... |
I can answer your first two questions.
> do ions upon discharging gain energy or lose energy?
Ions lose free energy during discharging, as you are referring to the spontaneous process of transferring charge at the electrodes with conversion into neutral species.
> are ions in general not less stable than neutr... |
I used chromatography to purify my protein and now I have fractions with different concentrations ranging from 1-16 mg/ml. Should I pool all these fractions or just the ones with high concentration (where under the actual peak)?
Thanks in advice
|
How to pool fractions after chromatography? |
Someone enjoys making jewelry, and saw an online tutorial saying that you can mix equal parts of vinegar and salt, and leave copper in it for a while to oxidize it, and turn it green.
After doing this, dumps the resulting solution down the drain, and runs the plastic cup it was done in through the dishwasher, presum... |
I can answer your first two questions.
> I am confused by 'require', do ions upon discharging gain energy or lose energy?
Ions lose free energy during discharging, as you are referring to the spontaneous process of transferring charge at the electrodes with conversion into neutral species (well, more generally yo... |
I can answer your first two questions.
> I am confused by 'require', do ions upon discharging gain energy or lose energy?
Ions lose free energy during discharging, as you are referring to the spontaneous process of transferring charge at the electrodes with conversion into neutral species (well, more generally yo... |
I can answer your first two questions.
> I am confused by 'require', do ions upon discharging gain energy or lose energy?
Ions lose free energy during discharging, as you are referring to the spontaneous process of transferring charge at the electrodes with conversion of some of the ions into neutral species (in ... |
For example, if gaseous oxygen $(O_2)$ and paraffin wax $(C_{32}H_{66})$ were to stoichiometrically combust at STP, how would one go about finding the heat capacity ratio ($\gamma={c_p \over c_v}$) of the resulting mixture of gases? I'm guessing that it involves finding the adiabatic flame temperature? (but idk how lol... |
How do you find the heat capacity ratio of combustion products? |
In my textbook, under the topic "Conditions for geometrical isomerism", the following has been given:
> Groups responsible to show geometrical isomerism must be nearly in the same plane.
Is this statement really true? Because, we are well aware that disubstituted cycloalkanes which show geometrical isomerism are ... |
I am considering labware options to handle NaOH solutions at ~150°C. One appealing idea would be to coat my current glassware with gold. I've read different sources mentioning the possibility without further detail.
The most detailed description of a process for this is [this pdf][1] by a manufacturer who sells (or ... |
In my textbook, under the topic "Asymmetric and Dissymmetric Compounds", the following statement is given:
> A molecule which does not possess plane of symmetry, centre of symmetry, and alternating axis of symmetry is called dissymmetric.
Why the definition didn't include the "axis of symmetry" as a condition for... |
When is it better to use coupled-cluster (CC) over configuration interaction (CI) calculations? |
I know the mathematical form of HUC and its statement i.e.It is impossible to determine simultaneously. , the exact position and momentum of an electron. i don't know why this principle exists. Moreover, i read that this all is not due to technique inadequancies, but due to the nature of electron. Wha... |
If cooking gas(or LPG) was exposed to some water in the gasline system, what would be the resultant by-product, and would this induce flame into the cylinder for explosion?
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/3kcnu.png |
Why is coke used as a reducing agent to reduce FeO to produce iron instead of coal.I admit that coke is carbonaceous but what is it that compels us to use coke instead of the naturally available coal? |
Why do we use coke instead of coal in order to reduce FeO as basic reaction in ironmaking process? |
My textbook explains applying Raoult's Law for the two cases:
i) liquid–liquid solutions:
In which the vapour pressure of the solution is due to both the components
AND
ii) non-volatile solids–liquid solutions:
In which the vapour pressure of the solution is only due to the liquid component of the solution
I am cur... |
If i have blood sample, organ tissue sample or food sample, what analytic technique is used in laboratory to detect the ppm levels of heavy metals? What electronic intrument they use? |
What instrument is used to detect heavy metals? |
I have seen Basicity to be calculated as B=wt%$CaO$/wt%$SiO_2$ particularly in slag bascity/acidity calcuations.Now I do not think that $CaO$ is the most basic oxide that we have or $SiO_2$ is the most acidic oxide then why are they calculated accordingly?On a lighter note in my geology classes I have been taught to cl... |
However what is so acidic about CaO and basic(no pun intended) about SiO2 while calculating basicity of slag? |
This problem came up while solving some problems on mass percentage and mole concept.
Essentially, our teacher said that the W/W% and the V/V% for a given solution will be the same, because in order to obtain V/V there will be a mutual division by density.
However, the density of solute is different from density ... |
Is the density of solute same as the density of solution? |
This problem came up while solving some problems on mass percentage and mole concept.
Essentially, our teacher said that the $w/w\%$ and the $v/v\%$ for a given solution will be the same, because in order to obtain $v/v\%$ there will be a mutual division by density.
However, the density of solute is different fro... |
If cooking gas (or LPG) was exposed to some water in the gasline system, what would be the resultant by-product, and would this induce flame into the cylinder for explosion?
[![Image][1]][1]
[1]: https://i.stack.imgur.com/3kcnu.png |
Does LPG (cooking gas) react with water? |
I have seen Basicity to be calculated as $\mathrm{B} = wt\%\:\ce{CaO}/wt\%\:\ce{SiO2}$ particularly in slag bascity/acidity calcuations. Now I do not think that $\ce{CaO}$ is the most basic oxide that we have or $\ce{SiO2}$ is the most acidic oxide then why are they calculated accordingly? On a lighter note in my geolo... |
My textbook explains applying Raoult's Law for the two cases:
1. liquid–liquid solutions, in which the vapour pressure of the solution is due to both the components
2. non-volatile solids–liquid solutions, in which the vapour pressure of the solution is only due to the liquid component of the solution
I am c... |
>One mole of solute ($\ce{NaCl}$) is dissolved in $\pu{1 L}$ of water. The molarity of the solution is:
>A) $\pu{<1M}$
>B) $\pu{>1M}$
>C) $\pu{=1M}$
>D) $\pu{=2M}$
**My answer:** It’s a fairly simple question so, I did what anybody would do.
$\mathrm{Molarity}=\frac{\text{No. of moles}}{\text{volume... |
Why is ethanol distilled off before adding water in the first step of a malonic synthesis? |
So, the temperature at which NOx is in equilibrium with its liquid and vapor phase at 1 atm is about -84C (Does that mean NOx exists as a liquid at that temperature? What about it's vapor phase then, because it's vapor and liquid phase should be at equilibrium right?).
Also, it's that the reason why compressed NOx whe... |
Why does a NOx container get cold when NOx is released? and What is the relationship of the vapor pressure curve with the liquid-vapor dome? |
With the Thermo-Fisher Fusion Orbitrap mass spectrometer I can do both CID (collision-induced dissociation) and HCD (higher energy C trap dissociation) collision-induced dissociation studies.
When I apply HCD on inorganic molecules I observe more fragmentation products than with just CID suggesting multiple fragmen... |
With the Thermo-Fisher Fusion Orbitrap mass spectrometer I can do both CID (collision-induced dissociation) and HCD (higher energy C trap dissociation) collision-induced dissociation studies.
When I apply HCD on inorganic molecules I observe more fragmentation products than with just CID suggesting multiple fragmen... |
Are there any 'conjugating agents' to accomplish the above transformation? If not, then how to proceed? |
How to convert 1,4 pentadiene to 1,3 pentadiene? |
Tell me, does table salt dissolve in glycerin? And is it possible to increase its solubility?
I have vegetable glycerin with nicotine that I use for vape. So that nicotine would not be bitter, on the forum I was advised to dissolve salt in it. But salt dissolves very poorly. How can I speed up this process? |
According to what i learned in university, the energy of orbitals increases when the principal quantum number n increases. Also, in a given shell, s orbitals have lower energy than p orbitals which have lower energy than d orbitals, which in turn have lower energy than f orbitals.
And according to Aufbau principle: "E... |
I can provide some physical intuition, but it's still going to require math and previous work to make it happen (aside on this at the end).
Let's consider a particle in just one dimension. There are two quantities of interest: (1) the position of the particle along this coordinate, (2) the scalar momentum (related t... |
I can provide some physical intuition, but it's still going to require math and previous work to make it happen (aside on this at the end).
Let's consider a particle in just one dimension. There are two quantities of interest: (1) the position of the particle along this coordinate, (2) the scalar momentum (related t... |
I have mostly come across examples of solids whose solubility increases in liquids with an increase in temperature. However, there seem to be exceptions to generalized rule this such as the solubility of Ce₂(SO₄)₃ in water. What makes this substance so special? |
Why is the binding angle of HOF(101°) lesser than that of H2O?(104.5°) Since flourine has unpaired electrons woudln't it repel hydrogen more strongly than a hydrogen repelling another hydrogen? |
Why is the binding angle of HOF lesser than that of H2O? |
I have mostly come across examples of solids whose solubility increases in liquids with an increase in temperature. However, there seem to be exceptions to generalized rule this such as the solubility of $\ce{Ce2(SO4)3}$ in water. What makes this substance so special? |
The neutralization reaction, such as HCl + NaOH → NaCl + H2O, generates heat, which is around 57.30 kJ/mol.
**Can we use this energy to design a battery?**
This idea occurs in my mind for a long time.
----------------------------------------------------
---------- **Selection for Acid and Base** -------------
... |
The neutralization reaction, such as $\ce{HCl + NaOH → NaCl + H2O}$, generates heat, which is around $\pu{57.30 kJ/mol}$.
**Can we use this energy to design a battery?**
This idea occurs in my mind for a long time.
----------------------------------------------------
---------- **Selection for Acid and Base** --... |
The reaction of benzene and γ-butyrolactone with AlCl<sub>3</sub> was reported by [Truce and Olson<sup>1][1]</sup> in 1952. The authors found that the ratio of γ-phenylbutyric acid to α-tetralone was dependent on the AlCl<sub>3</sub>/lactone ratio. The larger the latter ratio; the more α-tetral... |
The neutralization reaction, such as $\ce{HCl + NaOH → NaCl + H2O}$, generates heat, which is around $\pu{57.30 kJ/mol}$.
**Can we use this energy to design a battery?**
This idea occurs in my mind for a long time.
----------------------------------------------------
---------- **Selection for Acid and Base** --... |
Can you use something other than sodium chloride? Sodium bromide seems to be much more soluble in methanol:
Sodium chloride = [14.9 g/kg](https://en.m.wikipedia.org/wiki/Sodium_chloride)
Sodium iodide = [168 g/kg](https://en.m.wikipedia.org/wiki/Sodium_bromide)
A similar trend would be expected with other alc... |
This is the raman spectra of water. There is 1635 cm-1 Raman peak corresponding to HOH and 3410 cm-1 Raman peak corresponding to OH. But why is there general nonzero background in intensity? What caused it?
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/6KCkc.jpg |
This is the Raman spectrum of water. There is $\pu{1635 cm-1}$ Raman peak corresponding to $\ce{HOH}$ and $\pu{3410 cm-1}$ Raman peak corresponding to $\ce{OH}$. But why is there general nonzero background in intensity? What caused it?
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/6K... |
This is the Raman spectrum of water. There is $\pu{1635 cm-1}$ Raman peak corresponding to $\ce{HOH}$ and $\pu{3410 cm-1}$ Raman peak corresponding to $\ce{OH}$. But why is there general nonzero background in intensity? What caused it?
This is taken using 532nm wavelength raman system:
[![enter image description... |
Ammonium nitrate is one of the classic examples of an endothermic dissolution. People will usually explain why it's soluble by stating that the spontaneous dissolution process of ammonium nitrate is what drives the reaction, meaning that the obvious answer is **it's soluble because ΔG of dissolving it is negative**. ... |
What makes ammonium nitrate soluble? |
Ammonium nitrate is one of the classic examples of an endothermic dissolution. People will usually explain why it's soluble by stating that the spontaneous dissolution process of ammonium nitrate is what drives the reaction, meaning that the obvious answer is **it's soluble because ΔG of dissolving it is negative**. ... |
It would most likely be impossible to come up with a reliable measure of the volume of an orbital.
Orbitals are defined over all space, so an integral like this
$$
\iiint\phi(x,y,z)\,\mathrm dx\,\mathrm dy\,\mathrm dz
$$
is not guaranteed to be finite, and also doesn't really mean anything. Clearly, the orbital... |
Here is some data on other well-soluble salts:
[![http://wps.prenhall.com/wps/media/objects/946/969212/images/table11_2.gif][1]][1]
Comparing the values, both the anion and the cation contribute to magnitude of enthalpy and entropy. The larger cations seem to contribute to a larger entropy of dissolution, as do t... |
Here is some data on other well-soluble salts:
[![http://wps.prenhall.com/wps/media/objects/946/969212/images/table11_2.gif][1]][1]
Comparing the values, both the anion and the cation contribute to magnitude of enthalpy and entropy. The larger cations seem to contribute to a larger entropy of dissolution, as do t... |
Why is the binding angle of HOF(101°) lesser than that of H2O?(104.5°) Since fluorine has unpaired electrons wouldn't it repel hydrogen more strongly than the corresponding hydrogen of H2O? Also, the size of fluorine is bigger than hydrogen, which also should have made the repulsion greater. |
Why is the binding angle of HOF lesser than that of H2O, despite the lone pairs and size of the flourine? |
### In defence of Kekulé structures
The real answer is, in my view, much more nuanced than ron's answer would have one believe. I sincerely think it is too simplistic to just say that it is "wrong".
To understand what I mean, we need to look at the concept of a resonance hybrid, which is a weighted average of sev... |
I know that when both connecting and disconnecting battery jumper cables between two car batteries there is a prescribed safe way to do it. I can never remember the correct way because I can’t understand the reasoning behind the prescribed sequence. Is there an easy explanation / principle that can make this procedure ... |
What is the safest way to hook up car battery jump cables and why? |
I was examining data associated with [this post][1] on the heat of solution of ammonium nitrate when I came upon the [NIST ATcT data page][2] which lists the heat of formation of $\ce{(NH4)NO3(cr,l)}$. In this formula, what state does "(cr,l)" refer to?
The nearest I came to an explanation is an article (Ref. 1) by... |
What is the meaning of the state label (cr,l) appearing in NIST ATcT thermochemical data tables? |
I was examining data associated with [this post][1] on the heat of solution of ammonium nitrate when I came upon the [NIST ATcT data page][2] which lists the heat of formation of $\ce{(NH4)NO3(cr,l)}$. In this formula, what state does "(cr,l)" refer to?
The nearest I came to an explanation is an article (Ref. 1) by... |
What is the meaning of the phase state label (cr,l) appearing in NIST ATcT thermochemical data tables? |
No, the correct way of putting it is
$$\mathrm{Almost~all~of~the~\mathbf{inorganic}~nitrate~salts~are~soluble~in~water. }$$
The families of organic nitrate salts are typically nitrates of azoles and imidazoles. Some bright examples are (<i>R</i>) & (<i>S</i>)-miconazole nitrates, isoconazole nitrate and econazol ni... |
No, the correct way of putting it is
$$\mathrm{Almost~all~of~the~\mathbf{inorganic}~nitrate~salts~are~soluble~in~water. }$$
The families of organic nitrate salts are typically nitrates of azoles and imidazoles. Some bright examples are (<i>R</i>) & (<i>S</i>)-miconazole nitrates, isoconazole nitrate and econazol ni... |
I was examining data associated with [this post][1] on the heat of solution of ammonium nitrate when I came upon the [NIST ATcT data page][2] which lists the heat of formation of $\ce{(NH4)NO3(cr,l)}$. In this formula, what state does "(cr,l)" refer to?
The nearest I came to an explanation is an article (Ref. 1) by... |
What is the meaning of the phase state label (cr,l) appearing in ATcT thermochemical data tables? |
I was examining data associated with [this post][1] on the heat of solution of ammonium nitrate when I came upon the [NIST ATcT data page][2] which lists the heat of formation of $\ce{(NH4)NO3(cr,l)}$. In this formula, what state does "(cr,l)" refer to?
The nearest I came to an explanation is an article (Ref. 1) by... |
Compare the acidity of the following compounds:
CF3OH and CCl3OH.
My attempt: according to me CCl3 group will show a stronger Negative hyperconjugation effect than CF3, and thus would stabilize the anion more effectively. But the answer is CF3OH is more acidic.
What is wrong in my approach? |
>Compare the acidity of the following compounds: $\ce{CF3OH}$ and $\ce{CCl3OH}$.
My attempt: according to me $\ce{CCl3}$ group will show a stronger Negative hyperconjugation effect than $\ce{CF3}$, and thus would stabilize the anion more effectively.
But the answer is $\ce{CF3OH}$ is more acidic. What is wrong in... |
I was examining data associated with [this post][1] on the heat of solution of ammonium nitrate when I came upon the [NIST ATcT data page][2] which lists the heat of formation of $\ce{(NH4)NO3(cr,l)}$. In this formula, what state does "(cr,l)" refer to?
The nearest I came to an explanation is an article (Ref. 1) by... |
Why aerosol forms when you take a hot shower in a very cold day? |
I was examining data associated with [this post][1] on the heat of solution of ammonium nitrate when I came upon the [NIST ATcT data page][2] which lists the heat of formation of $\ce{(NH4)NO3(cr,l)}$. In this formula, what states does "(cr,l)" refer to?
[1]: https://chemistry.stackexchange.com/questions/119041/w... |
The nearest I came to an explanation is an article (Ref. 1) by authors of the database explaining that, in the case of $\ce{H2O (cr,l)}$, the notation (cr,l) refers to the condensed state. Also, [a link][1] from the above data page explains that "cr=crystal" and "l=liquid" (thanks MaxW for hinting at the solution).
... |
The nearest I came to an explanation is an article (Ref. 1) by authors of the database explaining that, in the case of $\ce{H2O (cr,l)}$, the notation (cr,l) refers to the condensed state. Also, [a link][1] from the above data page explains that "cr=crystal" and "l=liquid" (thanks MaxW for hinting at the solution).
... |
I have seen so many conflicting answers to this question in various places so I wanted to ask it again.
IUPAC defines a transition metal as:
> "an element whose atom has a partially filled d sub-shell, or which can give rise to cations with an incomplete d sub-shell"
By this definition, Scandium would be a transit... |
Is Scandium considered a transition metal? |
Why is the shape of fluorescence spectrum different between systems using 532nm and 785nm wavelength laser in Raman Spectroscopy? In the following using the 785nm RMX, the fluorescence is maximum at the left (starting at 100 cm-1) and minimum at the right (ending at 2750 cm-1).
[![enter image description here][1]][1... |
Why is the shape of fluorescence spectrum different between systems using 532nm and 785nm wavelength laser in Raman Spectroscopy? In the following using the 785nm RMX, the fluorescence is maximum at the left (starting at 100 cm-1) and minimum at the right (ending at 2750 cm-1).
[![enter image description here][1]][1... |
Why is the shape of fluorescence spectrum different between systems using 532nm and 785nm wavelength laser in Raman Spectroscopy? In the following using the 785nm RMX, the fluorescence is maximum at the left (starting at 100 cm-1) and minimum at the right (ending at 2750 cm-1).
[![enter image description here][1]][1... |
Note: I haven't owned any of these spectrometers. I'm asking so I can decide whether to buy 532nm or 785nm wavelength raman to probe molecular structure (especially solutions) and I'm concerned about fluorescence versus signal intensity. The first picture is from 16:00 minute time of this video https://www.youtube.com/... |
I know that when both connecting and disconnecting battery jumper cables between two car batteries there is a prescribed safe way to do it. I can never remember the correct way because I can’t understand the reasoning behind the prescribed sequence. Is there an easy explanation / (chemical?) principle that can make thi... |
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