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"In general, Friedel-Craft's alkylation is not employed to make monoalkyl benzene derivatives because of the polysubstitution." writes in our lab manual.
But our proffessor told us that while we are doing this experiment, polysubstitution is quite impossible.
Phenol + t-butyl chloride (AlCl3 catalyst)--> para-t-but... |
According to our lab manual:
> In general, Friedel–Craft's alkylation is not employed to make monoalkyl benzene derivatives because of the polysubstitution.
But our professor told us that while we are doing this experiment, polysubstitution is quite impossible.
[![Phenol + t-butyl chloride (AlCl3 catalyst)--> ... |
Why doesn't polysubstitution occur in this Friedel–Craft's alkylation reaction? |
According to our lab manual:
> In general, Friedel–Crafts alkylation is not employed to make monoalkyl benzene derivatives because of the polysubstitution.
But our professor told us that while we are doing this experiment, polysubstitution is quite impossible.
[![Phenol + t-butyl chloride (AlCl3 catalyst)--> p... |
Why doesn't polysubstitution occur in this Friedel–Crafts alkylation reaction? |
In the section on acid-catalysed hydrolysis of nitriles, [this][1] webpage has the following line of reasoning;
>...the more stable amide tautomer predominates the (following) equilibrium.
How are the relative stabilities of these tautomers compared? I made up a reason of the resonance structure for the amide one ... |
In the section on acid-catalysed hydrolysis of nitriles, [this][1] webpage has the following line of reasoning;
>...the more stable amide tautomer predominates the (following) equilibrium.
[![enter image description here][2]][2]
([credit][1])
How are the relative stabilities of these tautomers compared? I ... |
>What would the first step be in a reaction between acyl chloride and sodium acetate in the presence of acetic acid?
I'm a bit confused because I'm not quite sure which step would occur first. I was thinking that perhaps the sodium acetate will first attack the carbonyl carbon, but I'm also wondering if it would be ... |
According to our lab manual:
> In general, Friedel–Crafts alkylation is not employed to make monoalkyl benzene derivatives because of the polysubstitution.
But our professor told us that while we are doing this experiment, polysubstitution is quite impossible.
[![Phenol + t-butyl chloride (AlCl3 catalyst)--> p... |
I'm practicing for an exam and cant figure out why the answer written is true.
The density of a mixture of Nitrogen and Oxygen is 4.7 grams/L.
Its given that P = 4 atmospheres, and that T = 298 Kelvin.
Assuming both gasses are ideal gasses, what is the molar fraction of Nitrogen in this mixture?
The answer is 0.82. |
What is the molar fraction of N in the following problem? |
I'm practicing for an exam and cant figure out why the answer written is true.
The density of a mixture of Nitrogen and Oxygen is 4.7 grams/L.
Its given that P = 4 atmospheres, and that T = 298 Kelvin.
Assuming both gasses are ideal gasses, what is the molar fraction of Nitrogen in this mixture?
The answer is 0.82.... |
### Question
> The density of a mixture of Nitrogen and Oxygen is $\pu{4.7 g L-1}$.
Its given that $P = \pu{4 atm}$, and that $T = \pu{298 K}$. Assuming both gasses are ideal gasses, what is the molar fraction of nitrogen in this mixture?
### Answer
>! Mole fraction of nitrogen is 0.82.
### My Attempt
I... |
[![Nucleophile Electrophile orbital interaction][1]][1]
Clearly the above diagrams depict the interaction between empty orbital of electrophile with filled orbital of nucleophile. We may assume that the HOMO of nucleophile being more electronegative will have energy less than that of less electronegative electoph... |
I want to compare retention time of acetic acid(AA), salicylic acid(SA) and acetylsalicylic acid(ASA) in HPLC. What are the factors do I have to consider when comparing? Considering dipole moment only, retention time would be AA(1.74D) < SA(2.65D) < ASA(6.49D). Is this correct? |
I came across the following two details about m-xylene:
1. m-xylene is thermodynamically most stable compound among o-xylene, m-xylene and p-xylene.
2. m-xylene is most reactive towards nitration and sulphonation among the others.
I did some research and was able to find valid reasons for both the statements, ... |
I want to compare retention time of acetic acid(AA), salicylic acid(SA) and acetylsalicylic acid(ASA) in HPLC. What are the factors do I have to consider when comparing? Considering dipole moment only, retention time would be AA(1.74D) < SA(2.65D) < ASA(6.49D). Is this correct? (Addition : Mobile phase would be water) |
I came across the following two details about *m*-xylene:
1. *m*-Xylene is thermodynamically most stable compound among *o*-xylene, *m*-xylene, and *p*-xylene.
2. *m*-Xylene is most reactive towards nitration and sulphonation among the others.
I did some research and was able to find valid reasons for both the... |
I have read that Hydrogen Cyanide is emitted if Potassium Ferricyanide is combusted, but would this be the same case for Potassium Ferrocyanide? I am preparing to perform some case hardening on steel using a compound that contains 30-50% Potassium Ferrocyanide, so I need to be sure what measures are needed for protecti... |
What toxic gases are emitted during the combustion of potassium ferrocyanide? |
I mean (H20) is non-toxic and is needed every day but all of the other group 16 hydrides are toxic and flammable ,hydrogen sulfide (H2S) ,hydrogen selenide (H2Se),hydrogen telluride (H2Te) and hydrogen polonide (H2Po),but water is an outlier,why is this the case? |
Should uranium hexoxide exist? |
This compound of uranium called [uranium hexoxide][1] is a special type of uranium oxide. The uranium has an oxidation state of +12 ,the highest of any known chemical. The closest is the $\ce{[IrO4]+}$ cation with iridium having an oxidation state of +9 so this is obviously insane if this exists. It's also called urani... |
I mean ($\ce{H2O}$) is non-toxic and is needed everyday but all of the other group 16 hydrides (hydrogen sulfide ($\ce{H2S}$), hydrogen selenide ($\ce{H2Se}$), hydrogen telluride ($\ce{H2Te}$) and hydrogen polonide ($\ce{H2Po}$)) are toxic and flammable. We observe that water is an outlier. Why is this the case? |
Why are all of the group 16 hydrides/hydrogen chalcogenides except H2O toxic? |
[![Nucleophile Electrophile orbital interaction][1]][1]
Clearly the above diagrams depict the interaction between empty orbital of electrophile with filled orbital of nucleophile. We may assume that the HOMO of nucleophile being more electronegative will have energy less than that of less electronegative electoph... |
>Home science optical absorption test for approximate caffeine quantity in coffee?
Yes..., except that for "...in coffee?" it's **No.**
AAI Solutions' [Measuring Caffeine Concentration; Applied Analytics Application Note No. AN-019](https://aai.solutions/documents/AA_AN019_Measuring-Caffeine-Concentration.pdf) fr... |
Can the RDS be different in different direction in a multi-step reversible reaction? |
This video nicely explains your question.
https://youtu.be/INYZy6_HaQE
The essence is that paulis exclusion principle states that two electrons(or generally fermions) cannot occupy the same Quantum state.(This is because electrons are fundamentally indistinguishable,but their wavefunctions are not.so there must be so... |
It is often said that lithium follows the duet rule instead of the octet rule, in the sense that there is no practical difference in, say, energies or shapes of lithium-containing compounds, whether the lithium 2p orbitals are included in the calculation or not, unlike the case of "usual" main-group elements.
My que... |
### Question
> The combustion of benzene (l) gives $\ce{CO2(g)}$ and $\ce{H2O(l)}$. Given that the heat of combustion of benzene at constant volume is $\pu{-3263.9 kJ mol-1}$ at $\pu{25 ^\circ C}$; heat of combustion (in $\pu{kJ mol-1}$) of benzene at constant pressure will be: ($R = \pu{8.314 JK-1 mol-1}$)
### A... |
While finding the sum of change in entropy of the universe and thus defining Gibbs free energy, why is the change in entropy of surrounding the negative of enthalpy of the system divided by the temperature?
I mean why are we considering the pressure to be constant ( thus considering enthalpy) in all systems while ca... |
Why is enthalpy and not heat released by system used while calculating entropy of surroundings? |
I came across the following two details about *m*-xylene:
1. *m*-Xylene is thermodynamically most stable compound among *o*-xylene, *m*-xylene, and *p*-xylene.
2. *m*-Xylene is most reactive towards nitration and sulphonation among the others.
I did some research and was able to find valid reasons for both the... |
### Question
> The combustion of benzene (l) gives $\ce{CO2(g)}$ and $\ce{H2O(l)}$. Given that the heat of combustion of benzene at constant volume is $\pu{-3263.9 kJ mol-1}$ at $\pu{25 ^\circ C}$; heat of combustion (in $\pu{kJ mol-1}$) of benzene at constant pressure will be: ($R = \pu{8.314 JK-1 mol-1}$)
### A... |
My Textbook says:
> Two states A and B can never lie both on a reversible as will as irreversible adiabatic path. There lies only one unique adiabatic path linkage between two states A and B.
I don't understand what the book means. Why cannot there be both reversible and irreversible adiabatic paths between two ... |
Because $q=\Delta H$ only if only expansion work is done and the pressure of the system is constant. In that case, for an isothermal process, in which T is the same for system and surroundings, the entropy of the surroundings can be equated with the change in enthalpy divided by T. Which is why the applicability of the... |
My Textbook says:
> Two states A and B can never lie both on a reversible as will as irreversible adiabatic path. There lies only one unique adiabatic path linkage between two states A and B.
I don't understand what the book means. Why cannot there be both reversible and irreversible adiabatic paths between two ... |
>![enter image description here][1]
>
>From the list below, circle the wavelength that would be the best setting for the UV-visible spectrophotometer used to determine the FITC concentration in the sample.
> \begin{array} {}
\mathrm{wavelengths:} & \pu{400 nm}& \pu{450 nm}& \pu{500 nm}&\pu{550 nm} &\pu{600 nm}
\... |
### Question
> The combustion of benzene(l) gives $\ce{CO2(g)}$ and $\ce{H2O(l)}.$ Given that the heat of combustion of benzene at constant volume is $\pu{-3263.9 kJ mol-1}$ at $\pu{25 ^\circ C}$; heat of combustion (in $\pu{kJ mol-1}$) of benzene at constant pressure will be: $(R = \pu{8.314 J K-1 mol-1})$
### A... |
In Duma's method, we need to collect Nitrogen gas over water and subtract the aqueous tension. But why can we not just collect it over the air? |
Why is nitrogen gas collected over water? |
The production of bakelite using this method, but with an acid as the catalyst is simple enough; a protonation of the carbonyl oxygen, followed by an electrophilic substitution to the ring. The subsequent cross-linkage formation is the same for both cases, but I can't figure out how the initial reaction
steps would w... |
So I have some osmotic pressure data that I would like to obtain the second virial coefficient ($B_{22}$) for, but I am getting increasingly more confused on how the theory works. I know you can rewrite the expansion in the following manner:
$\Pi (T, c) = RT(c + B_{22}c^{2} + B_{23}c^{3} + ...)$
where $\Pi$ is t... |
The following reaction is specified in my notes;
$$\ce{CH4 ->[Mo2O3, \Delta]HCHO}$$ The intermediate steps involve the dehydration of an alcohol to yield the final product.
Wouldn't this only work if there's acid in the reaction mixture? Or is it that water functions as a proton donor, inducing the protonation of t... |
Dumas's method for determination of nitrogen (and usually then for estimation of protein content) is fairly old (1831 Ref 1) and has been modified to be quick and automatable. In the original method, the equipment was arranged to collect the gaseous nitrogen after passing thru various traps. The picture (Ref 2) shows a... |
Concerning the simplest approximation for intermolecular distance in solution:
$d=(\frac{10^{24}}{cN_A})^{1/3}=1.18c^{−1/3}$
This applies for one type of molecule in solution. But, how to account for two different molecules A and B of different concentrations?
My case: I have molecule A of 0,4 uM and molecule B ... |
What is the average distance of two different types of molecules of different concentrations in solution? |
[This video](https://youtu.be/INYZy6_HaQE) nicely explains your question.
The essence is that paulis exclusion principle states that two electrons(or generally fermions) cannot occupy the same quantum state.
This is because electrons are fundamentally indistinguishable,but their wavefunctions are not. So there ... |
It is often said that lithium follows the duet rule instead of the octet rule, in the sense that there is no practical difference in, say, energies or shapes of lithium-containing compounds, whether the lithium $2p$ orbitals are included in the calculation or not, unlike the case of "usual" main-group elements.
My q... |
It is often said that lithium follows the duet rule instead of the octet rule, in the sense that there is no practical difference in, say, energies or shapes of lithium-containing compounds, whether the lithium $2 \mathrm p$ orbitals are included in the calculation or not, unlike the case of "usual" main-group elements... |
I have a bunch of structures and of each I would like to find the largest cyclic substructure.
I'm not a chemist, so I don't know if there is a common terminology for this. I hope, I made it clear what I'm looking for.
Example:
[![enter image description here][1]][1]
Each structure on the top (1,2,3) as input... |
How to find the largest cyclic substructure with RDKit? |
What is an appropriate way to write a recursive SMARTS that excludes trifluoromethyl groups as a potential R group? |
In 1928, Malaprade demonstrated that periodic acid reacted with ethylene glycol to produce iodic acid and formaldehyde (Ref.1). Hence, the oxidation of adjacent diols with periodic acid or its salt in aqueous solution is now generally known as the Malaprade reaction, the mechanism of which is depicted below:
[![Peri... |
**I think chlorine trifluoride deserves a mention**
One of the issues with relying on published NPFA triangles to judge the answer to this question is that some of them don't seem to be very reliable given the known properties of compounds.
[According to one of its suppliers][1] ClF<sub>3</sub> has a rating of 4-... |
I'm trying to dimension a flash drum for a separation between water and isobutane. I now the total inlet flow (F), the composition of the inlet flow ($z_1$ for isobutane and $z_2$ for water) and the total pressure (P). My supervisor told me that if my inlet flow to the flash was gas I would want my flash drum to operat... |
Why do we want to operate at dew point or bubble point when doing flash calculations? |
A lot of the organometallics are rather... interesting compounds to work with. The most famous (among those who care, anyway) is *tert*-butyllithium or t-BuLi. It is the textbook example of a pyrophoric substance, demonstrated to pretty much every chemistry major as an air-sensitive chemical requiring special handling ... |
I use CA glue† very frequently in my shop, but I'm not entirely sure how it works. I've noticed three main modes of curing, I've emphasised the key observations:
1. When dispensed, it will remain fluid until even **a small amount of pressure is applied**. With pressure, it will set and cure in 5 - 45 seconds. Often,... |
How does (E)CA glue ("super glue", "crazy glue", etc.) cure? |
Why is melting point of $\ce{Mg3N2}$ lower than that of $\ce{Be3N2}$ ?
I have two reasonings: <br>
1) The lattice energy of $\ce{Be3N2}$ is higher than that of $\ce{Mg3N2}$ so accordingly the melting point of the former should be higher <br>
2) Both of them form ionic nitrides. Since $\ce{Mg3N2}$ has more <b>ioni... |
Here I am confused regarding which reaction shall take place. Does ether cleavage occur or electrophilic addition of HI to the double bond take place or both? The answer that I have says C is right but I'm equally inclined towards D. [![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/ogJYq.p... |
Why is melting point of $\ce{Mg3N2}$ lower than that of $\ce{Be3N2}$ ?
I have two reasonings: <br>
1) The lattice energy of $\ce{Be3N2}$ is higher than that of $\ce{Mg3N2}$ so accordingly the melting point of the former should be higher <br>
2) Both of them form ionic nitrides. Since $\ce{Mg3N2}$ has more <b>ioni... |
Why is melting point of Mg3N2 lower than that of Be3N2? |
I use CA glue† very frequently in my shop, but I'm not entirely sure how it works. I've noticed three main modes of curing, I've emphasised the key observations:
1. When dispensed, it will remain fluid until even **a small amount of pressure is applied**. With pressure, it will set and cure in 5 - 45 seconds. Often,... |
I use CA glue† very frequently in my shop, but I'm not entirely sure how it works. I've noticed three main modes of curing, I've emphasized the key observations:
1. When dispensed, it will remain fluid until even **a small amount of pressure is applied**. With pressure, it will set and cure in 5 - 45 seconds. Often,... |
I use CA glue† very frequently in my shop, but I'm not entirely sure how it works. I've noticed three main modes of curing, I've emphasized the key observations:
1. When dispensed, it will remain fluid until even **a small amount of pressure is applied**. With pressure, it will set and cure in 5 - 45 seconds. Often,... |
### Problem
> The products formed in the reaction
>
> $$\ce{CH2=CHOCH2CH3 + HI ->}$$
>
> are
>
> (**a**) $\ce{CH2=CHI}$ and $\ce{CH3CH2I}$
> (**b**) $\ce{CH2=CHI}$ and $\ce{CH3CH2OH}$
> (**c**) $\ce{CH3CHO}$ and $\ce{CH3CH2I}$
> (**d**) $\ce{CH3CH(I)OCH2CH3}$
### Answer
>! (**c**) $\ce{CH3CHO}... |
I understand that carbon normally only have up to 4 bonds and the R and S are designed for 4 bonds. Is there a similar convention of 'chirality' for an atom with 5 bonds? |
Is chirality defined for 5 bonds? |
I understand that carbon normally only have up to 4 bonds and the R and S are designed for 4 bonds. Is there a similar convention of 'chirality' for an atom with 5 bonds?
From the SMILES website (section 3.3.4 General Chiral Specification), it seems they do exist (general 'chirality' for 6 bonds also exists). But th... |
I understand that carbon atoms normally only have up to 4 substituents and the R and S chirality centers are defined for 4 substituents. Is there a similar convention of 'chirality' for an atom with 5 substituents?
From the SMILES website (section 3.3.4 General Chiral Specification), it seems they do exist (general ... |
Is chirality defined for an atom with 5 substituents? |
Amongst CH3O- and CN- CN- is a better nucleophile than CH3O- in polar protic solvent while CH3O- is better one in polar aprotic solvent because in polar aprotic solvent CH3O- is free to move and O- has more electron density.
Does this same reason apply for OCH3- and SCH3-, is OCH3- a stronger nucleoplhile than the lat... |
I understand that carbon atoms normally only have up to 4 substituents and the R and S chirality centers are defined for 4 substituents. Is there a similar convention of 'chirality' for an atom with 5 substituents?
The SMILES website (section 3.3.4 General Chiral Specification) shows that general 'chirality' for 5 a... |
Between $\ce{CH3O-}$ and $\ce{NC-}$, $\ce{NC-}$ is a better nucleophile than $\ce{CH3O-}$ in polar protic solvent while $\ce{CH3O-}$ is better one in polar aprotic solvent because in polar aprotic solvent $\ce{CH3O-}$ is free to move and $\ce{O-}$ has more electron density.
Does this same reason apply for $\ce{CH3O-... |
How is chirality center defined for an atom with 5 substituents? |
I understand that carbon atoms normally only have up to 4 substituents and the R and S chirality centers are defined for 4 substituents. Is there a similar convention of 'chirality' for an atom with 5 substituents?
The SMILES website (section 3.3.4 General Chiral Specification) shows that general 'chirality' for 5 a... |
What happens if you add pure food grade lactic acid to fresh pasteurized milk? What chemical reactions would take place? Does smell and taste like sour milk? Or like yoghurt? |
What happens if you add pure food grade lactic acid to fresh pasteurized milk? |
Is Chromium (VI) fluoride possible? |
Between $\ce{CH3O-}$ and $\ce{NC-}$, $\ce{NC-}$ is a better nucleophile than $\ce{CH3O-}$ in a polar protic solvent, while $\ce{CH3O-}$ is a better one in a polar aprotic solvent, because in a polar aprotic solvent $\ce{CH3O-}$ is free to move and $\ce{O-}$ has more electron density.
Does the same reason apply for $... |
Are solvent effects the reason for the methoxide ion to be a stronger nucleophile than the thiomethoxide ion? |
What happens if you add pure food grade lactic acid to fresh pasteurized milk? What chemical reactions would take place? Does it smell and taste like sour milk? Or like yoghurt? |
Welcome to ChemistrySE.
In short: is the spectrum consistent with 3-methyl-1-butanol? No. The triplet splitting and integral of the signal at 0.86ppm is inconsistent with an isopropyl sidechain. This suggests a methyl group attached to a methylene, $\ce{-CH2-CH3}$.
The signal at $\pu{3.6 ppm}$ has a chemical shi... |
If an elementary reaction was conducted in the gaseous phase, say $\ce X (g) \longrightarrow Y(g)$ , would the formal definition of the elementary rate law be $rate = kP_X$ or $rate = k[X]$? |
I mean ($\ce{H2O}$) is non-toxic and is needed everyday but all of the other group 16 hydrides (hydrogen sulfide ($\ce{H2S}$), hydrogen selenide ($\ce{H2Se}$), hydrogen telluride ($\ce{H2Te}$) and hydrogen polonide or polonium hydride ($\ce{H2Po}$) are toxic and flammable. We observe that water is an outlier. Why is th... |
The ambiguity doesn't lie so much in the definition of the *rate*, because as long as the constants $a$ and $b$ in $ap_\ce{X}$ and $b[\ce{X}]$ are chosen appropriately, the two expressions are entirely equivalent. So you can define the rate either way, and there is no physical difference, not even a mathematical differ... |
The ambiguity doesn't lie so much in the definition of the *rate*, because as long as the constants $a$ and $b$ in $ap_\ce{X}$ and $b[\ce{X}]$ are chosen appropriately, the two expressions are entirely equivalent. So you can define the rate either way, and there is no physical difference, not even a mathematical differ... |
If an elementary reaction was conducted in the gaseous phase, say $$\ce{X (g) -> Y(g)},$$ would the formal definition of the rate law be $\mathrm{rate} = kP_\ce{X}$ or $\mathrm{rate} = k[\ce{X}]$? |
Should rates and rate constants be expressed in terms of pressure or concentration? |
The ambiguity doesn't lie so much in the definition of the *rate*, because as long as the constants $a$ and $b$ in $ap_\ce{X}$ and $b[\ce{X}]$ are chosen appropriately, the two expressions are entirely equivalent. So you can define the rate either way, and there is no physical difference, not even a mathematical differ... |
In the [mechanism][1] for the Wolff-Kishner reduction, after the $\ce{OH-}$ abstracts a proton, the resulting negative charge delocalises away from the nitrogen atom to the carbon, and the subsequent protonation occurs to the carbon.
[![enter image description here][2]][2]
[![enter image description here][3]][3]
... |
In the [mechanism][1] for the Wolff-Kishner reduction, after the $\ce{OH-}$ abstracts a proton, the resulting negative charge delocalises away from the nitrogen atom to the carbon, and the subsequent protonation occurs to the carbon.
[![enter image description here][2]][2]
[![enter image description here][3]][3]
... |
I understand how to find the valency of atoms in small organic compounds. For instance, for CH4, the valency of carbon is 4, while the valency of each hydrogen is 1. But for a coordination complex, for instance:
[![enter image description here][1]][1]
**How do I find the valency of the center metal?**
And if t... |
What does the acidity of phenol depend on? |
If an atom had 200 protons, how much neutrons would it need to have to be most likely stable and why? |
In cyclic voltammograms (like the one in the attached image) what exactly is the horizontal axis' voltage refering to? Is it the measured voltage between the reference electrode and working electrode? If so, and assuming the measurements are made with a standard voltmeter, which electrode is considered the cathode and ... |
What does the horizontal axis on cyclic voltammograms mean? |
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