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[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/Wwxzb.png
(a)Why would cyclohexane expand into cycloheptane? cyclohexane is stable.
(b)Why would cyclopentane not ring expand into cyclohexane? In the process a tertiary carbocation would be formed just like with the methyl shift, but you... |
Can someone explain my professor's answers for these alkene additions? |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/keexL.png
In my lab course, I am doing an experiment on the rate of reaction, but all three of my trials were using the same temperature. That would just result in a straight vertical line, correct? |
Is the graph that is attached (a form of the arrhenius equation) only used when the temperature is varied? |
Old question, but interesting topic. I don't intend to reply, but rather to add some relevant info. There is no "one" copper acetate. There are many, some neutral, some basic. They all follow the rule $$\ce{[Cu(CH3COO)2]_x·[Cu(OH)2]_y·nH2O}$$ in which $x ≥ 1, \; y ≥ 0$, and $n ≥ 0$ (*i.e.*, with ratios $x:y:n$, being *... |
I was interested in an application of Le Chatelier's Principle, where an increase in pressure could result in a decrease in the moles of gas.
In particular, a situation where when the pressure increased, it drove the reaction in one direction (towards fewer moles), but when the pressure was lower, then the reactio... |
I was interested in an application of Le Chatelier's principle, where an increase in pressure could result in a decrease in the moles of gas.
In particular, a situation where when the pressure increased, it drove the reaction in one direction (towards fewer moles), but when the pressure was lower, then the reactio... |
Can 1,3-butadidyne show conjugation in both the free p orbitals ?
As 2c and 3c are sp hybridized so there are two unhybridised p orbital mutually perpendicular to each other in each of carbon atom also these two orbitals are separated by a sigma bond.
There is possibility that it could show conjugation from the **bo... |
> Which is more reactive towards electrophilic substitution, *meta*-cresol or *para*-cresol?
Both oxygen and methyl are activating groups. I don't know on what basis do I compare their reactivity. There's just a change in the position of one of the group.
My book says *meta*-cresol is more reactive and the reaso... |
Is m-cresol or p-cresol more reactive towards electrophilic substitution? |
A common highschool chemistry example for the polarity of water is the experiment where stream of water is deflected under the influence of a charge (electric field).
Now I have come across some condradicting claims, namely this Youtube video from [Veritasium](https://youtu.be/1Xp_imnO6WE?t=109) (from around 1:50) a... |
Can buta-1,3-diyne show conjugation in both the free p orbitals?
As 2c and 3c are sp hybridized so there are two unhybridised p orbital mutually perpendicular to each other in each of carbon atom also these two orbitals are separated by a sigma bond.
There is possibility that it could show conjugation from the *... |
To start, it is important that you understand that the methyl and hydroxy groups are activating only in the ortho and para positions. For example, if I were to substitute plain phenol, which contains an activating hydroxy group, which position would my electrophile (in this a bromine electrophile) add to? You can see t... |
When we heat water, we see bubbles appear as the boiling point approaches. The water then "boils" vigorously as it is converted from the liquid phase to a gas.
I realised recently that during an ether extraction of a product, a lot of ether had evaporated, as was evident from the mass balance. The ether vapours were... |
[![enter image description here][1]][1]
[![enter image description here][2]][2]
determine the approximate value of Ea with its appropriate units.
[![enter image description here][3]][3]
In my lab course, I am doing an experiment on the rate of reaction, but all three of my trials were using the same temperature... |
Can buta-1,3-diyne show conjugation in both the free p orbitals?
As 2c and 3c are sp hybridized so there are two unhybridised p orbital mutually perpendicular to each other in each of carbon atom also these two orbitals are separated by a sigma bond.
Is There a possibility that it could show conjugation from the... |
Sorry for the confusing title, I didn't know how to describe this better. So, if we douse rubber, say, a bicycle tire or a certain type of rubber glove, with organic solvent (n-heptane), we can find n-alkanes being dissolved in the solvent. Why is this? I'm talking especially about gas chromatography to analyse the par... |
[![enter image description here][1]][1]
(a) Why would cyclohexane expand into cycloheptane? Cyclohexane is stable.
(b) Why would cyclopentane not ring expand into cyclohexane? In the process a tertiary carbocation would be formed just like with the methyl shift, but you would also get rid of ring strain.
(c) W... |
I read in my chemistry textbook that Lithium carbide is the only carbide amongst Alkali metals. As we know Carbides are ionic compounds & Calcium carbide is predominantly ionic( Calcium having similar electronegativity value to Lithium).
So is the bond between Lithium and Carbon ionic? Or is it covalent? |
Is Lithium carbide an ionic compound or covalent? |
I read in my chemistry textbook that lithium carbide is the only carbide amongst alkali metals. As we know, carbides are ionic compounds, and calcium carbide is predominantly ionic (calcium having similar electronegativity value to lithium).
So, is the bond between lithium and carbon ionic? Or is it covalent? |
Is lithium carbide an ionic compound or covalent? |
> This linear polyatomic ion containing three atoms of carbon has a negative four charge and is only found bonded with lithium and magnesium.
Could anyone identify this for me? It's from a quiz bowl clue that doesn't have the answer with it. |
I was interested in an application of Le Chatelier's principle, where an increase in pressure could result in a decrease in the moles of gas.
In particular, a situation where when the pressure increased, it drove the reaction in one direction (towards fewer moles), but when the pressure was lower, then the reactio... |
I use a mineral based fertilizer in powder form which - according to the label - should not contain any fiber and is fully soluble in water (I dissolved 2 times the recommended dosage and found no solids remaining in the solution):
[![NPK fertilizer label][1]][1]
The NPK + Mg + trace elements add up to about 60... |
Why can DAP be used to elute a protein in affinity chromatography? |
I read in my chemistry textbook that lithium carbide (Li4C) is the only carbide amongst alkali metals. As we know, carbides are ionic compounds, and calcium carbide is predominantly ionic (calcium having similar electronegativity value to lithium).
So, is the bond between lithium and carbon ionic? Or is it covalent? |
If someone smokes, exhales the smoke, then what exactly is coming out, and which of these parts---such as smoke molecules, breath, air, etc.---are going where how far?
Please explain in a clear language suitable for a non-chemist. |
What exactly spreads how far, if cigarette smoke is exhaled? |
Why does Pubchem show cis-1,3-Cyclohexanediol with the hydroxyls in the equatorial position? |
From Klein's *Organic chemistry* \[1, p. 780\]:
> The 1,2-adduct is believed to form more rapidly as a result of a *proximity effect*. Specifically, the carbocation and the bromide ion are initially very close to each other immediately after their formation in the first step of the mechanism. The bromide ion is simp... |
Why does Pubchem show cis-1,3-cyclohexanediol with the hydroxyls in the equatorial position? |
I was interested in an application of [Le Chatelier's principle][1], where an increase in pressure could result in a decrease in the moles of gas.
In particular, a situation where when the pressure increased, it drove the reaction in one direction (towards fewer moles), but when the pressure was lower, then the re... |
I was interested in an application of [Le Chatelier's principle][1], where an increase in pressure could result in a decrease in the moles of gas.
In particular, a situation where when the pressure increased, it drove the reaction in one direction (towards fewer moles), but when the pressure was lower, then the re... |
I dont know why i cant draw $[HCO_3]^{-}$ like that :
i tried to draw it like that checked everything .
```
O--O
\
C=O
/
H
i checked formal charge and all was good
why they draw it OH i know its also alright but whats wrong with my draw ? 24e checked and formal ch... |
I dont know why i cant draw $[HCO_3]^{-}$ like that :
i tried to draw it like that checked everything .
```
O--O
\
C=O
/
H
i checked formal charge and all was good
why they draw it OH i know its also alright but whats wrong with my draw ? 24e checked and formal ch... |
I dont know why i cant draw $[HCO_3]^{-}$ like that :
i tried to draw it like that checked everything .
```
O--O
\
C=O
/
H
i checked formal charge and all was good
why they draw it OH i know its also alright but whats wrong with my draw ? 24e checked and formal ch... |
I dont know why i cant draw $[HCO_3]^{-}$ like that :
i tried to draw it like that checked everything .
```
O--O
\
C=O
/
H
i checked formal charge and all was good
why they draw it OH i know its also alright but whats wrong with my draw ? 24e checked and formal ch... |
Who said you couldn’t? You absolutely can. What you have shown is [performic acid][1] (or at least its conjugate base). Just to clarify, it is obviously different to [carbonic acid][2].
[1]: https://pubchem.ncbi.nlm.nih.gov/compound/Performic-acid
[2]: https://pubchem.ncbi.nlm.nih.gov/compound/Carbonic-acid |
I don't know why can't I draw $\ce{[HCO3]-}$ like that:
[![[HCO3]-][1]][1]
I tried to draw it like that and checked everything.
I checked formal charge and all was good.
Why they draw it OH I know its also alright but whats wrong with my draw? 24e checked and formal charge checked.
The upper left oxygen has 6 ... |
Who said you couldn’t? You absolutely can. What you have shown is [performic acid][1] $\ce{CH2O3}$ (or at least its conjugate base). Just to clarify, it is obviously different to [carbonic acid][2] $\ce{H2CO3}$.
[1]: https://pubchem.ncbi.nlm.nih.gov/compound/Performic-acid
[2]: https://pubchem.ncbi.nlm.nih.go... |
An aqueous solution of $\ce{HCl}$ has a $\mathrm{pH}$ of $0.00$ if $[\ce{H+}] = 1.00 \; \mathrm{M}$. I tried to see if an aqueous solution of acetic acid could have a $\mathrm{pH}$ of $0.00$, given that its $K_a$ value is $1.8 \times 10^{-5}$. I tried finding the concentration $[\ce{H+}]$ of such a solution using
$$... |
> A $\pu{0.45 M}$ solution of a weak acid, $\ce{HX}$, has a $\pu{pH}$ of $4.5$. What is the ionization constant, $K_a$, of the acid?
- $\ce{[HX]}$ is already given as $\pu{0.45 M}$.
- $\ce{[H+]}$ is given by $10^{-4.5}$.
Since $\ce{pH}$ is $4.5$, $\ce{pOH} = 14 - 4.5 = 9.5$. Then we can get $\ce{[OH^-]}$ by com... |
How to find the ionization constant of an unknown weak acid? |
Look at the answer given here and modify it:
[How to set up equation for buffer reaction?](https://chemistry.stackexchange.com/a/95566/)
In your case the concentration of base $c_B \approx 0$ and $[\ce{OH^-}] = K_\mathrm{w}/[\ce{H^+}] \approx 0$, so that the equation reduces to $$K_\mathrm{a} = \frac{[\ce{H^+}]^2}{... |
I want to know what happens to that breath. To help you answer this question, consider in your mind these subquestions:
- Is there a necessary principle at work, by which you know that it vanishes/solves into the air after a set amount of time or distance?
- Is it attached to the smoke, and does it travel with it?
... |
If cigarette smoke is exhaled, what happens to the accompanying exhaled breath? |
Take the reaction:
N2(g)+3H2(g)⟷2NH3(g)
If pressure is decreased, equilibrium shifts to the left because it has more moles. I understand the basics of why this is, i.e. due to Le Chatelier's principle, but is there an actual explanation as to why the system does this (e.g. using collision theory)? What's actually... |
What exactly causes equilibrium to shift when pressure is decreased? |
Polystyrene plastic can be melt in acetone.
I would like to understand:
1)If the melting polystyrene will take-out of the acetone
and becomes solid again(after all the acetone evaporates),
Will this solid polystyrene keep the same material properties as it was
before the melting process?
2)How can i speed-up the... |
Polystyrene plastic can be melt in acetone.
I would like to understand:
1. If the melting polystyrene will take-out of the acetone and becomes solid again (after all the acetone evaporates), will this solid polystyrene keep the same material properties as it was before the melting process?
2. How can I speed-up th... |
Take the reaction:
$$\ce{N2(g) + 3 H2(g) <=> 2 NH3(g)}$$
If pressure is decreased, equilibrium shifts to the left because it has more moles. I understand the basics of why this is, i.e. due to Le Chatelier's principle, but is there an actual explanation as to why the system does this (e.g. using collision theory)... |
I have been studying the molecular orbital theorem. I read that the energy levels for the $\ce{p}$ orbitals in the first series of $\ce{p}$ block molecules are something to the tune of $$\pi_x=\pi_y<\sigma_z<\pi_x^*=\pi_y^*<\sigma_z^*$$
except for $\ce{O2 and F2}$, which have
$$\sigma_z<\pi_x=\pi_y<\pi_x^*=\pi_y^*... |
I want to know what happens to that breath. To help you answer this question, consider in your mind these subquestions:
- Is there a necessary principle at work, by which you know that it vanishes/solves into the air after a set amount of time or distance?
- Is it attached to the smoke, and does it travel with it?
... |
I've searched online, but have not found anyone that has experienced the same.
I have a 20 gallon plastic tub with a lid.
In it keep plastic shopping bags.
Also had a box of detergent in there.
I witnessed over time, the fumes (I am guessing) from the detergent affected the plastic bags.
The big 20 gallon bin is f... |
I was wondering about sulfur as an alternative life-threatening chelators. Why isn't sulfur used as a chelator if heavy metals have an affinity for it? |
If heavy metals bind to sulfur why isn't sulfur used as a safer way to chelate them? |
What is the explanation of barreled spirits (at 62.5% ethanol) that undergo changes in concentration of ethanol. Whereas the volume after aging is typically reduced, the proof varies between low 100 to low 140 (50-70%). Does the presence or formation of azeoptopes play a role?
I contend that the barrel interface is im... |
I read in my chemistry textbook that lithium carbide (Li4C) is the only carbide amongst alkali metals. As we know, carbides are ionic compounds, and calcium carbide is predominantly ionic (calcium having similar electronegativity value to lithium).
So, is the bond between lithium and carbon ionic? Or is it covalent?
... |
I was reading [this] and it mentions in the 3-electron section, that for a spacial wave function to be symmetric under fermion swapping, it must be a function of even parity. Similarly for anti-symmetry under fermion swapping, it must be a function of odd parity.
It is not immediately obvious to me why parity symmet... |
So, another question from my side.
I have been thinking about the folowing reaction:[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/rlzjj.png
The reaction above exists and was already done on two occasions and reportedly works really well and it seems to be a no-brainer to me as well. No... |
Alkylation before ring closure? |
Can somebody please explain the mechanism of Peptization(or give a link to the website which explain the mechanism step by step). The Mechanism given in my book is somewhat different from the mechanism given on the Wikepedia. Also the Wikepedia one is baffling me.
Also, how does coagulation differ from peptization. ... |
today I reacted tin iodide (dissolved in water) with hydrogen peroxide, this produced a yellow/ brown colour (I'm guessing due to formation of I2?). I then added some petroleum spirit which gave a dibasic system which was a clear/ pink colour on top and an orangey brown yellow underneath. I'm struggling to find out wha... |
Today I reacted tin(IV) iodide $\ce{SnI4}$ (dissolved in water) with hydrogen peroxide. This produced a yellow/brown colour (I'm guessing due to formation of $\ce{I2}?).$
I then added some petroleum spirit which gave a dibasic system which was a clear/pink colour on top and an orangey brown yellow underneath.
I'm... |
**Phase change is not at constant temperature, phase equilibrium is**
>[OP] it's a phase transition so the temperature of the ice should remain constant
Here is a counter example: If you add ice cubes to hot water, the ice will melt, cooling down the hot water. In this system, there is no thermal equilibrium, so ... |
Can somebody please explain the mechanism of Peptization(or give a link to the website which explain the mechanism step by step). The Mechanism given in my book is somewhat different from the mechanism given on the Wikepedia. Also the Wikepedia one is baffling me.
The wikipedia [Peptization][1] states
>The electri... |
Is there way to test erythritol vs sugar? I'm very hypoglycemic and use erythritol. But the latest bag I bought gives me headaches, and I'm wondering if it's been diluted with sugar. |
From what I understand, Hartree-Fock simplifies the exact electron-electron interaction with its two electron integrals. It reminds me of the classical energy of a charge distribution combined with the multipole expansion. Is it valid to think of it in this way? |
Can Hartree-Fock be considered the quantum mechanical "Monopole" term in a quantum mechanical multipole expansion? |
I was wonder what it was specifically that make things such as Lexapro safe when it came to its Flouride and nitrile bonds. Why doesn't Lexapro break down into cyanide? Is it just minimal because the chemical is so large it has more mass? Is it like just priming genetic code so that it will chemically metabolize into a... |
Today I reacted tin(IV) iodide $\ce{SnI4}$ (dissolved in water) with hydrogen peroxide. This produced a yellow/brown colour (I'm guessing due to formation of $\ce{I2}?).$
I then added some petroleum spirit which gave a bi-phasic system which was a clear/pink colour on top and an orange-brown yellow underneath.
I'... |
Today I reacted tin(IV) iodide $\ce{SnI4}$ (dissolved in water) with hydrogen peroxide. This produced a yellow/brown colour (I'm guessing due to formation of $\ce{I2}?).$
I then added some petroleum spirit which gave a bi-phasic system which was a clear/pink/ light purple colour on top and an orange-brown yellow und... |
I was wonder what it was specifically that make things such as Lexapro safe when it came to its Fluoride and nitrile bonds. Why doesn't Lexapro break down into cyanide? Is it just minimal because the chemical is so large it has more mass? Is it like just priming genetic code so that it will chemically metabolize into a... |
How to calculate Revelle factor using only pH , DIC and TAlk for seawater? |
I have the temperature, salinity, pH, Dissolved Inorganic Carbon and Total Alkalinity values for an estuarine water sample. I want to calculate the Revelle factor. The Revelle factor can be calculated from the Partial pressure of CO2 and Dissolved inorganic carbon. But I don't have the value for partial pressure of CO... |
Since the question raised a discussion in the comments, I guess it won't hurt putting up a brief summarizing answer.
Notation % m/v, as you might've guessed, refers to the ratio between the **m**ass and the **v**olume, or, more precisely, [mass concentration](https://en.wikipedia.org/wiki/Mass_concentration_(chemist... |
How to calculate Revelle factor using only pH, DIC and TAlk for seawater? |
Since the question raised a discussion in the comments, I guess it won't hurt putting up a brief summarizing answer.
Notation % m/v, as you might've guessed, refers to the ratio between the **m**ass and the **v**olume, or, more precisely, [mass concentration](https://en.wikipedia.org/wiki/Mass_concentration_(chemist... |
Does ice get colder when you add salt? |
Another way to look at the problem:
If we add $\ce{H+}$ to the water through adding acid, then some of the $\ce{H+}$ would just remain in the solution as is, and some of them would react with $\ce{OH-}$ in the reaction $\ce{H+ + OH- -> H_2O}$. How much of the added $\ce{H+}$ reacts? To calculate this, you need to... |
I was asked to give the equilibrium expression for:
$$\ce{CO2(aq) + H2O(l) <=> H2CO3(aq)}$$
As water is a liquid and a solvent here, it shouldn't be included in the expression, hence I wrote:
$$K_c = \frac{[\ce{H2CO3}]}{[\ce{CO2}]}$$
However, the answer of the question included water in the denominator.
... |
I know that when you put salt on ice it may turn to a slush and it does feel cold. What is the reason for this? |
Why does ice get colder when you add salt? |
Since the question raised a discussion in the comments, I guess it won't hurt putting up a brief summarizing answer.
Notation % m/v, as you might've guessed, refers to the ratio between the **m**ass and the **v**olume, or, more precisely, [mass concentration](https://en.wikipedia.org/wiki/Mass_concentration_(chemist... |
What is the heaviest element of the periodic table for which there is a compound whose Crystal structure has been completely resolved by X-ray diffraction? |
What is the heaviest element of the periodic table for which there is a compound whose crystal structure has been completely resolved by X-ray diffraction? |
why is an alkyne substituent on ben zene electron withdrawing but alkane and alkene are electron donating? |
Is it okay to use copper sulphate in an evaporative humidifier to prevent mould growth? |
Why is an alkyne substituent on benzene is electron withdrawing, but alkane and alkene are electron donating? |
If I dissolve the weak acid HCN into water, I get a solution of oxonium and CN ions and since there is an equilibrium there is more HCN left.
So I thought CN ions can consequently react with water to form hydroxide-ions, which is a weak base-reaction, by which we also get the original HCN molecules.
I am confused ... |
How do you know is a solution is acid or basic when you dissolve a weak acid/base? |
I am currently designing a synthesis requiring the use of hydroxy protecting groups. The problem I am having is that the protecting group must be able to survive highly acidic conditions. I would have loved to use a TMBS protecting group since it can withstand LAH, lewis acids, and strong base; however, not acidic cond... |
a racemic mixture has 50-50% of the 2 different enantiomers. There are racemate drugs out there in the world. The misunderstanding I have is that usually 1 out of the 2 enantiomers molecules have a different reaction with the body, so if you perform racemisation to form a racemic mixture, ain’t that drug going to be st... |
EDIT: This is not a homework problem and we need this for an exploratory study on teeth demineralization. There is further work planned around this activity, which may not be relevant to the question.
For this purpose, few publications have quoted the use of Ca/PO4/acetate solution containing 2mmol/L calcium, 2 mmo... |
There are plenty of compounds out there with unknown standard molar entropies. I know that molar entropy has a strong dependance on the physical phase, molecular weight, and number of atoms. So is it feasible to use these parameters to roughly estimate the molar entropy of, for example, ammonium acetate? |
I recently read a paper by Lyulin et al. \[[1](https://doi.org/10/ggcghf)\] where they talk about thin films and bulk polymers, I just don't quite understand what they mean by "bulk". Can someone please explain?
### References
1. Lyulin, A. V.; Balabaev, N. K.; Baljon, A. R. C.; Mendoza, G.; Frank, C. W.; Yoo... |
What does bulk mean when talking about polymers? |
What happens to the equilibrium when an **increase in pressure** is applied to a system with the **same number of moles of gas** on both sides of the reaction, according to Le Chatelier's Principle?
For example:
$$
\ce{2 HBr (g) <--> H2 (g) + Br2 (g)}
$$
|
[![enter image description here][1]][1]
(a) Why would cyclohexane expand into cycloheptane? Cyclohexane is stable.
(b) Why would cyclopentane not ring expand into cyclohexane? In the process a tertiary carbocation would be formed just like with the methyl shift, but you would also get rid of ring strain.
(c) W... |
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