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First post here, what chemical could dissolve plastic aside from acetone? Preferably, low-cost and environmentally friendly? Any suggestions would be helpful.. |
What chemical could dissolve plastic? |
What chemical could dissolve plastic aside from acetone? Preferably, low-cost and environmentally friendly. Any suggestions would be helpful.
I'm targeting for thin plastic (low-density polyethylene). Environmentally friendly for me is that it follows the EPA standards from the USA. I'm targeting for around 150 USD.... |
What chemical could dissolve low-density polyethylene? |
If I mix xNaOH + yCdCl2 + zZnCl2, how can I calculate the final equilibrium quantities of the resulting salts (which I suppose may be the following):
Q1 NaOH
Q2 CdCl2
Q3 ZnCl2
Q4 NaCl
Q5 Cd(OH)2
Q6 Zn(OH)2
Also (only if it will take more than an hour for >99.999% of the reaction to occur), how ca... |
How can I calculate the equilibrium between several reactions? |
> The most important are π*orbitals as they are lower in energy than σ*orbitals and the carbonyl group (C=O) is the most important of these—indeed it is the most impor-tant functional group of all. *~Clayden, Chapter 5*
Why is it that Carbonyl Groups in organic chemistry are given so much importance ?? I am still in h... |
Activated carbon (AC) is one of the most widely used media for water filtration. It's effective at removing chlorine taste and odor, and it's recognized as being safe.
However, most activated carbon filters have a lifespan of about 4-6 months, after which they need to be replaced. But is there any risk to using an A... |
The following question was given in an exam.Which of the following undergo aldol condensation ?
Given answer : a,b,c
[![enter image description here][1]][1]
My answer: b,c
My Logic :
Cyclopenta-2,4-dienecarbaldehyde(**1**) on reaction with a base gives carbanion whose resonance structures are **1a to 1e... |
Will cyclopenta-2,4-dienecarbaldehyde undergo aldol condensation? |
[2-Methyl-But-1,3-diene][1]
$$\ce{2-Methyl-But-1,3-diene + HBr \rightarrow ??}$$
So in this , what I understand is that Carbon (2) will get a positive charge after protonation.
But after this, which should be the major product?
$\bullet$ 2-bromo-2-methyl-but-3-ene - because in this case the carbocation would b... |
What is the product of the reaction of 2-methyl-but-1,3-diene with HBr?
[![2-methyl-but-1,3-diene][1]][1]
What I understand is that carbon (2) will get a positive charge after protonation.
But after this, which should be the major product?
- 2-bromo-2-methyl-but-3-ene - because in this case the carbocation ... |
What is the major product of the reaction of 2-methyl-but-1,3-diene with HBr? |
Activated carbon (AC) is one of the most widely used media for water filtration. It's effective at removing chlorine taste and odor, and it's recognized as being safe.
However, most activated carbon filters have an indicated lifespan of about 4-6 months, after which they need to be replaced. But is there any risk to... |
[2-Methyl-But-1,3-diene][1]
$$\ce{2-Methyl-But-1,3-diene + HBr \rightarrow ?}$$
So in this , what I understand is that Carbon (2) will get a positive charge after protonation.
But after this, which should be the major product?
$\bullet$ 2-bromo-2-methyl-but-3-ene - because in this case the carbocation would be... |
> Is this something that has been explored in research?
Definitely yes, and the keywords you're looking for are: adsorption, desorption, and fluid transport in porous media. Activated carbon is a nanoporous material with high specific surface area, and the kinetics of adsorption, desorption and transport in liquid p... |
What is the product of the reaction of 2-methyl-but-1,3-diene with HBr?
[![2-methyl-but-1,3-diene][1]][1]
What I understand is that carbon (2) will get a positive charge after protonation.
But after this, which should be the major product?
- 2-bromo-2-methyl-but-3-ene - because in this case the carbocation ... |
What is the major product of the reaction of 2-methyl-but-1,3-diene with HBr? |
> The most important are π *orbitals as they are lower in energy than σ* orbitals and the carbonyl group (C=O) is the most important of these—indeed it is the most important functional group of all. *~Clayden, Chapter 5*
Why is it that Carbonyl Groups in organic chemistry are given so much importance? I am still in ... |
I have to solve an excercise that I've been trying for a long time without success.
Information that I have:
- pH @ certain temperature of an aquous dissolution of an acid
- molar concentration of the acid
Unknown:
- approximate $pKa$ (is not ment to be calculated with calculator i supose that is the ... |
Difference in major product of sulphonation of phenols
When phenol is sulphonated by fuming sulfuric acid at a lower temperature,the ortho product is the major whereas at higher temperature the para product is formed as the major.
Why does this happen , because looking at the reaction mechanism , it appears to me tha... |
After dealing with a leak from a 73kg compressed chlorine gas cylinder at 6 bar - there was green powder/rust/discoloration on the stainless steel tubing similar to copper chloride or copper sulphate - any thoughts of what this might be ? |
I am aware that some "Super Absorbent Polymers" can swell up enormously when they absorb water. However, I am looking for a material which swells up (maybe about 30% to 100%) when in a moist environment, and which will contract again when moved to a less moist environment.
I.E. by measuring the expansion of the mate... |
What materials reversably swell up slightly when in a moist environment? |
When phenol is sulphonated by fuming sulfuric acid at a lower temperature, the *ortho* product is the major whereas at higher temperature the *para* product is formed as the major.
Why does this happen, because looking at the reaction mechanism, it appears to me that *para* should always be the major.
Is it the ... |
* [Mass-action ratio](https://en.wikipedia.org/wiki/Mass%E2%80%93action_ratio)
* [Reaction quotient](https://en.wikipedia.org/wiki/Reaction_quotient)
According to their definitions expressed in the above Wikipedia articles, these two concepts seem to be totally identical. Is that true? If not, what is the differenc... |
Is “mass-action ratio” identical to “reaction quotient?” |
[![enter image description here][1]][1]
How are diagrams such as above plotted? Since empirical studies are slightly off from the 'ideal', what is the source for the phase plots?
[1]: https://i.stack.imgur.com/Lo9qp.png |
How are phase transition diagrams calculated? |
* The safest solvent might be [supercritical carbon dioxide][1], $\ce{CO2}$. [Supercritical carbon dioxide][2] is also used in "green" dry-cleaning. Use for dissolving polymers requires a pressure vessel for ~5 to 50 MPa, able to work at ~40 to 100°C. There are (paywalled) articles at [ACS][3] and [NCBI][3], if you wan... |
I am trying to reproduce the quantity referred to as the *degree of charge transfer* reported in this publication by [Zhu et al.](http://sci-hub.tw/10.1021/cm201798x) for the F4-TCNQ molecule. I am interested in section 3.2 in the main text about using the bond length as an estimate for the charge transfer amount.
... |
How to calculate the amount charge transfer from a natural population analysis? |
The problem to solve is this: I want to create a heat generator [or heat absorber] that functions at atmospheric pressure to the pressure at the bottom of the sea. It will be used to drive a Stirling engine.
As such, I'm worried that a simple burner with adjustable flow rates won't act predictably at extreme pressur... |
Do fuel/oxidizer combustion mechanics change when the constituents are supercritical? |
How do fuel/oxidizer combustion mechanics change when the constituents are supercritical? |
The hydrazine molecule, and the similar sulfonium/Oxonium ylides, all have a gauche conformation that is more stable than the anti conformation.
Is there any particular reason for this pattern? Orbital Interactions in Chemistry tries to use overlap between the 2 “lone pair” orbitals on the carbons as a justificatio... |
After dealing with a leak from a 73 kg compressed chlorine gas cylinder at 6 bar, there was green powder/rust/discoloration on the stainless steel tubing similar to copper chloride or copper sulphate. Any thoughts of what this might be? |
> Consider the following reversible reaction.
> $$\ce{Cr2O7^2-(aq) + H2O(l) <=> 2 CrO4^2-(aq) + 2 H+(aq)}$$
> What will happen to the position of equilibrium and the value of $K_c$ when more $\ce{H+}$ ions are added at constant temperature?
> $$
\begin{array}{lcc}
\hline
& \text{Position of equilibrium} &... |
> For a chemical reaction
> $$\ce{2 A + 2 B -> C + D}$$
> the order of reaction is one with respect to $\ce{A}$ and one with respect to $\ce{B}$. The initial rate of the reaction is $\pu{4e-2 mol L-1 s-1}.$ When $50\%$ of the reactants are converted into products, the rate of the reaction would become
> (**A**... |
How electric field work inside a battery? |
> Is this the right formula to use to solve the above problem
Yes, this is it, if the initial concentrations of the reagents are the same (which is _not_ mentioned explicitly in the problem statement, but probably is implied, because otherwise the problem would be unsolvable.)
Indeed, as A and B are spent in equa... |
What materials reversibly swell up slightly when in a moist environment? |
CH3COOC2H5+NaOH→CH3COONa+C2H5OH
What different areas about solvents can be explored with the conductivities collected of the alkaline hydrolysis of ethyl acetate in propanone and ethanol?
Currently, I am looking at the effect on activation energy, rates, and rate constants and the overall conversion of ethyl aceta... |
This question is not very mighty. But I'm having a problem wrapping my head around the Bohr's atomic structure. The textbook says electrons revolve around the nucleus in fixed energy shells, with each shell having its different value for energy. What I want to know is, what does it mean for a shell to have an energy le... |
User @Poutnik has recently answered two questions([here][1] and [here][2]) in which he quoted this statement from Wikipedia:
> Almost all metals can form amalgams with mercury, the notable
> exceptions being iron, platinum, tungsten, and tantalum.
I am not sure about the validity of this statement as I found con... |
Does tantalum and tungsten really not form amalgams? |
User @Poutnik has recently answered two questions([here][1] and [here][2]) in which he/she quoted this statement from Wikipedia:
> Almost all metals can form amalgams with mercury, the notable
> exceptions being iron, platinum, tungsten, and tantalum.
I am not sure about the validity of this statement as I found... |
I read that the equilibrium constant is unitless because the molar activities of each of the species are used in the equilibrium expression, not the actual concentrations themselves. I understand that.
But it is taught that $K_c = \frac{k_{forward}}{k_{backward}}$. I’m having some difficulty understanding this equatio... |
Why is the equilibrium constant unitless? |
This is a complicated question among chemical educationists- with tons of arguments over arguments. Just search do equilibrium constant have units? I would say the "units" of K are in a grey area (just like in any real world science.). You should read the nice section on [Dimensionality of the Equilibrium Constant][1],... |
Think of the planetary system which inspired Bohr to think about his atomic model. The Earth is rotating around the Sun in a fixed orbit. What keeps the Earth rotating around the Sun? The mechanics of the planetary motion, and other electrical phenomena were very well understood in Bohr's time, so much so that by late ... |
There are several ways to answer the question, so here are my three. The first answer involves using a simple integer wavelengths approximation, i.e., noticing that Figs. 1 and 2 have 1 nm point spacing, and then using a spreadsheet to perform a summation. The answer explained in this part also serves to define the ter... |
Are portable pen pHmeters accurate? |
Would this experiment be electrolysis experiment be viable? |
If I mix xNaOH + yCdCl2 + zZnCl2 in an aqueous medium, how can I calculate the final equilibrium quantities of the resulting salts (which I suppose may be the following):
Q1 NaOH
Q2 CdCl2
Q3 ZnCl2
Q4 NaCl
Q5 Cd(OH)2
Q6 Zn(OH)2
Also (only if it will take more than an hour for >99.999% of the react... |
I'd like to prepare a solution of Ca(OH)2 from CaO.
Ideally I guess I'd go for slowly adding the powder to a water-cooled round flask containing pure water but I have no mechanism to control the slow release of powder nor am I sure that the reaction wouldn't be fast enough to send the powder right back out of the f... |
Safe & Convenient method to hydrate CaO into Ca(OH)2? |
I have to solve an exercise that I've been trying for a long time without success.
Information that I have:
> - pH @ certain temperature of an aqueous dissolution of an acid
> - molar concentration of the acid
Unknown:
> - approximate $\mathrm{p}K_\mathrm{a}$ (is not meant to be calculated with calculato... |
I'd like to prepare a solution of $\ce{Ca(OH)2}$ from $\ce{CaO}$.
Ideally I guess I'd go for slowly adding the powder to a water-cooled round flask containing pure water but I have no mechanism to control the slow release of powder nor am I sure that the reaction wouldn't be fast enough to send the powder right bac... |
Are pen $\mathrm{pH}$-meters accurate? I know there are large table-top $\mathrm{pH}$-meters, but I keep seeing these small $\mathrm{pH}$-meters online that can read up to 0.1 units. My question is if these $\mathrm{pH}$-meters (look pretty cheap) are accurate or should I get the large table-top $\mathrm{pH}$-meter for... |
Are portable pen pH-meters accurate? |
What type of material is used in the control rod of a nuclear reactor? (Nuclear power plant) |
Cyclic polyynes have been proposed as [theoretical compounds](https://pubs.acs.org/doi/10.1021/ed200439u) to illustrate the “particle on a ring” model discussed in many quantum chemistry courses. I've looked it up on [Wikipedia](https://en.wikipedia.org/wiki/Cyclocarbon) but there it's not clear whether one has ever be... |
Your instinct about not rounding early is good. Before I get to that, I wanted to address one thing in another answer:
"> I learned that the absolute and relative error have only 1 significant figure
That really isn't true. In your example you showed 5.34532g ± 0.001428g which could result from some kind of exper... |
Thank you very much. Now I am gonna insert the values and show you what I get. I have no clue if it makes sense or not.
I start with an aquous dissolution of $H_2SO_3$. I know it will dissociate in two steps, however I read in a book that the first dissociation is normally the strongest and almost every time you ca... |
I find myself in quite a pinch: I have to sustain a Chemical Physics exam, and I know for a fact that the professor often asks this particular question:
"Suppose that we have both a reacting species and an inhibitor in a homogeneous solution, and we insert a solid catalyst in it. What is the equation that describes th... |
What is the equation that describes the variation in concentration of an inhibitor in an heterogeneous catalysis? |
Thank you very much. Now I am gonna insert the values and show you what I get. I have no clue if it makes sense or not.
I start with an aquous dissolution of $\ce{H2SO3}$. I know it will dissociate in two steps, however I read in a book that the first dissociation is normally the strongest and almost every time you... |
In a home brewing project, I use washing soda (Na<sub>2</sub>CO<sub>3</sub>) to remove labels and glue from previously used bottles. In doing this, my flip-top bottles (which have a stainless steel flip top arm) often get unruly buildup of residual soda, which tarnishes and blemishes the steel. **Is there a chemical mi... |
$$\ce{CH3COOC2H5 + NaOH -> CH3COONa + C2H5OH}$$
What different areas about solvents can be explored with the conductivities collected of the alkaline hydrolysis of ethyl acetate in propanone and ethanol?
Currently, I am looking at the effect on activation energy, rates, and rate constants and the overall conversio... |
User @Poutnik has recently answered two questions([here][1] and [here][2]) in which he/she quoted this statement from Wikipedia:
> Almost all metals can form amalgams with mercury, the notable
> exceptions being iron, platinum, tungsten, and tantalum.
I am not sure about the validity of this statement as I found... |
User @Poutnik has recently answered two questions([here][1] and [here][2]) in which he/she quoted this statement from Wikipedia:
> Almost all metals can form amalgams with mercury, the notable
> exceptions being iron, platinum, tungsten, and tantalum.
I am not sure about the validity of this statement as I found... |
As per laws of constant proportion/Proust's law,Ratio of elements by mass is always constant.
But in case of
H2+O2 →H2O
Here when the chemists might have measured H2 and O2 individually they might have get a total mass of 2g+32g=34g
And on measuring the product that is H2O they might get a mass of 2g+16g=18g
Hence,h... |
Well sorry if this questions sounds incorrectly asked on this site. This is my first question here and I didnt get where to ask it on stackexchange. Anyway, let me just ask:
> Is there any harm involved in keeping copper water bottles in fridege / refrigerator?
Few days back, in summer, I carried [kokum](https://... |
What is the ultimate reason, that the electrons cannot occopy the p-orbitals of the K shell?
So, why for example, there is no element having electron configuration 1s21p3? And is it possible to exite the electron(s) of hydrogen or helium to the 1p-orbital(s)? |
Open cardboard boxes/crates, often for foodstuffs, are often glued to hold their shape. What is the glue made?
I ask to know if it is biodegradable (for composting/gardening).
My preliminary research seems to indicate polyvinyl acetate (PVA), which seems to biodegrade fast enough for my application.
See exampl... |
What are glues for cardboard boxes/crates made of? |
What is the ultimate reason, that the electrons cannot occupy the p-orbitals of the K shell?
Why for example, is there no element having electron configuration 1s<sup>2</sup> 1p<sup>3</sup>? And is it possible to excite the electron(s) of hydrogen or helium to the 1p-orbital(s)? |
Waht is the reason the electrons cannot occupy p-orbitals of the K shell? |
As per laws of constant proportion/Proust's law,Ratio of elements by mass is always constant.
But in case of
H2+O2 →H2O
Here when the chemists might have measured H2 and O2 individually they might have get a total mass of 2g+32g=34g
And on measuring the product that is H2O they might get a mass of 2g+16g=18g
I know ... |
I want to learn to develop novel methods in computational chemistry (e.g. Grimme's empirical dispersion, DFTB, new DFT functionals, etc.) What is the ideal way to learn this by oneself?
I have read books on the Hartree-Fock theory and I understand it to some degree. However, there seems to always be a large amount o... |
I have heard two definitions for metamers.
1. Compounds having the same molecular formula but **different number of carbon atoms** on either side of functional group.
2. Compounds having the same molecular formula but **different alkyl groups** on either side of functional group .
Which one of these are correct?
... |
Which is the correct definition for metamers (or metamerism)? |
I have heard two definitions for metamers.
1. Compounds having the same molecular formula but **different number of carbon atoms** on either side of functional group.
2. Compounds having the same molecular formula but **different alkyl groups** on either side of functional group .
Which one of these are correct?... |
during my experiments I want the emitted laser beams to come back with a different wavelength than the original wavelength using a fluorescent foil / fluorescent film. Therefore I want to ask if any of you know a company, research institute or similar where I can get a fluorescent foil/ film?
Or what kind of dyes can ... |
Fluorencence - Does anybody of you know a company, research institute or similar where I can get a fluorescent foil/ fluorescent film? |
I have built an rv from a short school bus. I ran a hose from the "toilet" to a tank in the back to drain the toilet. We wash our dishes in a basin on the counter and dump the dishwater into the toilet to also drain into the tank. I am getting a tannish/white build up in the hose that is plugging the line and not lett... |
what does the mixture between urine and dishwater cause? |
There is no IUPAC definition for metamers or metamerism in the gold book (not even one that makes it obsolete), and Wikipedia doesn't even have a real article about it, see [Metamerism](https://en.wikipedia.org/wiki/Metamerism).
> In chemistry, the chemical property of having the same proportion of atomic components... |
Given Question :- Give isomeric relations between these compounds. https://imgur.com/a/yq9vKf9
My answer :- https://imgur.com/a/mRF78GC
Given answer :- https://imgur.com/a/kqx8I3C
My doubt :-
How does A and C & B and C show positional isomerism?
Does positional isomerism even makes sense when the carbon chain ske... |
### Question
> Give isomeric relations between these compounds.
> [![enter image description here][1]][1]
### My answer
- **A** and **B** show metamerism and positional isomerism.
- **A** and **C** show chain isomerism and metamerism.
- **B** and **C** show chain isomerism and metamerism.
### Given ... |
How hot will a carbon electrode get in an electrolysis setup? |
during my experiments I want the emitted laser beams to come back with a different wavelength than the original wavelength using a fluorescent foil / fluorescent film.
The laser I'm currently using has a wavelength of 632,8nm. The color of the emitted beams doesn't matter (it can have every color).
Therefore I wan... |
Fluorencence - Does something like fluorescent foil/ fluorescent film exist? |
Well sorry if this question sounds incorrectly asked on this site. This is my first question here and I didn't get where to ask it on stackexchange. Anyway, let me just ask:
> Is there any harm involved in keeping copper water bottles in fridge/refrigerator?
Few days back, in summer, I carried [kokum](https://en.... |
During my experiments I want the emitted laser beams to come back with a different wavelength than the original wavelength using a fluorescent foil or fluorescent film.
The laser I'm currently using has a wavelength of 632.8 nm. The color of the emitted beams doesn't matter (it can have every color).
Therefore I ... |
Does something like a fluorescent foil or a fluorescent film exist? |
User @Poutnik has recently answered two questions([here][1] and [here][2]) in which he/she quoted this statement from Wikipedia:
> Almost all metals can form amalgams with mercury, the notable
> exceptions being iron, platinum, tungsten, and tantalum.
I am not sure about the validity of this statement as I found... |
As per laws of constant proportion/Proust's law,Ratio of elements by mass is always constant.
But in case of
H2+O2 →H2O
Here when the chemists might have measured H2 and O2 individually they might have get a total mass of 2g+32g=34g
And on measuring the product that is H2O they might get a mass of 2g+16g=18g
... |
I have heard two definitions of metamers.
1. Compounds having the same molecular formula but **different number of carbon atoms** on either side of the functional group.
2. Compounds having the same molecular formula but **different alkyl groups** on either side of the functional group.
Which one of these is cor... |
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