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The problem likely is not (so much) the plastic material of your container, either solid, or bag.*) Assuming there is no contamination on the outer side of the container, most likely the smells are noticed because of _closing_ the container by either knot or lid is not tight enough.
After some search on sibling sit... |
See if your group or an other (e.g., organic / organic catalysis) has a [Schlenk line][1]. With some training, this allows you to reduce the interference of oxygen greatly, because you may evacuate your reaction flasks and to replace the air by an inert gas such as nitrogen or argon. Nitrogen is relatively cheap beca... |
The problem is:
> A quantity if 35.2g if a certain hydrocarbure gas, occupies 13.2L, measured at 1atm and at 323K. Knowing that 85.5% of is C, find the molecular formula for the hydrocarbure.
$\textbf{Attempt.}$ So I tried with the first step doing $0.85\cdot 35.2g=29.92g\text{ of C}$ and I'm pretty sure that's ... |
Okay, just to give an idea of my current understanding. Reforming is a step one can do after one has cracked some hydrocarbons. As such, the process of reforming is dependent on a separate process, cracking. What it involves is cracking the hydrocarbons, then putting them together in new ways, whilst still having the s... |
Is reforming and isomerization the same thing? |
The problem is:
> A quantity if 35.2g if a certain hydrocarbure gas, occupies 13.2L, measured at 1atm and at 323K. Knowing that 85.5% of is C, find the molecular formula for the hydrocarbure.
$\textbf{Attempt.}$ So I tried with the first step doing $0.85\cdot 35.2g=29.92g\text{ of C}$ and I'm pretty sure that's ... |
**Main Question:** Where can I find a table (or realistic formula) for isopropanol/water %vol/vol **mixes** and corresponding freezing temperature with public access?
**Background:**
Trying to get the freezing point of my car windshield wash fluid.
**What I have tried so far:**
Anti-freeze is may be ethanol or... |
The problem is:
> A quantity of $\pu{35.2 g}$ if a certain hydrocarbon gas, occupies $\pu{13.2 L}$, measured at $\pu{1 atm}$ and at $\pu{323 K}$. Knowing that 85.5% of is C, find the molecular formula for the hydrocarbon.
**Attempt.** So I tried with the first step doing $0.85\cdot \pu{35.2 g} = \pu{29.92 g}$ of... |
The problem is:
> A quantity of $\pu{35.2 g}$ if a certain hydrocarbon gas, occupies $\pu{13.2 L}$, measured at $\pu{1 atm}$ and at $\pu{323 K}$. Knowing that 85.5% of is C, find the molecular formula for the hydrocarbon.
**Attempt.** So I tried with the first step doing $0.85\cdot \pu{35.2 g} = \pu{29.92 g}$ of... |
I am a retired man and seek for activity. I dont have background in chemistry but I want to learn an aluminum battery..the known problem is my aluminum metal get eaten and also corrosion even if using sodium electrolite and worse if using Aluminum chloride.
So I just try PAC for water treatment and it look like the ... |
I continuously soak this natural quartz (it is originally white) in basin of water and salt, it has a metal on it too.
What caused the green stuff?
How to remove it?
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/1hqwP.jpg |
The goal here is to isolate the sugar from all other compounds in the juice. In this case, I'm using apple juice and grape juice. The sugar does not need to be edible, as it is being used to make r-candy. Boiling off the water from the juice doesn't work in this particular application, since the syrup is still contamin... |
Can I extract solid sugar from any fruit juice at home? |
once in my class test I was asked which mechanism would be followed by a certain reaction with good leaving group.
it was a MCQ
with options
1 E1 reaction
2 E2 reaction
3 E1cb
4 both E1 and E2
*I answered 4* because **they both occur simultaneously the main difference comes in the amount of product f... |
My teacher frequently gives us questions where we have to arrange the given binary compounds on basis of their melting points or solubilities. He did give us some instructions in order to judge this order. But they don't seem to work for any questions. I asked a senior student as to how to tackle this problem, and he s... |
Don't worry too much about it, this educational exercise will be over when the exam is over. In real life nobody can predict the melting point or solubility in water just by looking at the structure of a given molecule. There are software like ACD, ChemDraw and SciFinder database which have predicted melting points and... |
Can Fe and Ca react and become unusable in some foods? |
Let's look at scheme [![RHF][1]][1]
Do I understand correctly, the origin of Virtual Orbitals is a solution of (for, exampre, restricted) HF equation eigenfuncions?
[1]: https://i.stack.imgur.com/CxDOe.png |
how does the retro Diels–Alder reaction explain this molecule formation? |
> Which mechanism would be followed by a certain reaction with good leaving group?
>
> 1. E1
> 2. E2
> 3. E1cB
> 4. both E1 and E2
I answered 4 because they both occur simultaneously. The main difference comes in the amount of product formed by them.
For this I was awarded with negative marks. Can anyone ple... |
I seem to have a drain pipe in my flat blocked by what seems to be a latex/rubber glove. I am unable to pull it out — is there a chemical that can reliably dissolve the glove and at the same time not damage the PVC pipe itself? |
once in my class test I was asked which mechanism would be followed by a certain reaction with good leaving group.
it was a MCQ
with options
1 E1 reaction
2 E2 reaction
3 E1cb
4 both E1 and E2
*I answered 4* because **they both occur simultaneously the main difference comes in the amount of product... |
This is really a plumbing issue much more than a chemical dissolution issue. The problem is uncertain: "seems" to be a latex rubber glove; complete blockage.
I'm trying to envision how a rubber glove completely blocks a drain. Perhaps by partially blocking the drain, then catching hair and other particles - but on ... |
I was looking at the synthesis of corallopyronin A in the following paper by Rentsch and Kalesse: [*Angew. Chem. Int. Ed.* **2012,** *51* (45), 11381–11384](https://doi.org/10.1002/anie.201206560).
There is one reaction which is described as
> oxidation and a retro Diels–Alder reaction generated pyrone
[![en... |
My textbook makes this claim but I can't find any info about it online or elsewhere. The chapter is on water purification and hard/soft water.
My thoughts are to either 1) to aid purification of urine for consumption 2) to remove ions from water that has been poisoned 3) to purify water that may be polluted due to a... |
Why did soldiers in WW2 carry small ion exchange resin columns in their survival kits? |
My textbook [Chemistry Live, Declan Kennedy] states that ''During WW2 small ion exchange resin columns were part of a soldier's survival kit.''. I can't find any further info about this online or elsewhere. The chapter is on water purification and hard/soft water.
My thoughts are to either 1) to aid purification of ... |
once in my class test I was asked which mechanism would be followed by a certain reaction with good leaving group.
it was a MCQ
with options
1 E1 reaction
2 E2 reaction
3 No reaction
4 both E1 and E2
*I answered 4* because **they both occur simultaneously the main difference comes in the amount of ... |
Which substance is best suited as a pH indicator for titration of 15 mL of 0.1 M ascorbic acid (K a = 7.9 * 10 -5 ) with 1.0 M sodium hydroxide solution?
Using the image below to find the best suited substance.
My progress: pka = -log(7.9*10^-5) so pka = 4.102
then pH = 4.102 + log(0.1/1) = 3.102
I am quite su... |
> Which substance is best suited as a pH indicator for titration of $\pu{15 mL}$ of $\pu{0.1 M}$ ascorbic acid $(K_\mathrm{a} = \pu{7.9E-5})$ with $\pu{1.0 M}$ sodium hydroxide solution?
> Using the image below to find the best suited substance.
>
> [![indicators pH range][1]][1]
My progress:
$$\mathrm{p}K_\ma... |
For what chemical purpose did soldiers in WW2 carry small ion exchange resin columns in their survival kits? |
On the face of it it doesn't seem especially difficult.
Model the amino acids as solid objects linked together. Approximate the 3D force fields around them using a coarse approximation, then set the simulation going in a computer and see what happens.
Why is this such a difficult problem that it has taken decades t... |
How would I make a basic protein folding algorithm? |
Why is the gradient of the curve of a strong base titrated with strong acid small up until equivalence? |
In short: Joining amino acids to build proteins _does not_ just assemble rigid bodies together.
Maybe you think it is joining a carboxylic acid and an amine to form an amide and to identify a conformation corresponding to the global energetic minimum around this unit. It surly was not this easy to enter successfull... |
Do you know the origin of the sample? Prior to deposit into tab water, was the sample already this green (e.g., a photo taken with the same color temperature of the light source [use of a color checker is seldom seen, even in institutions dealing with optics]) back then as now or / and UV-Vis reflectance spectrum? Fo... |
I am just wondering, can I make a metalorganic or organometallic complex of copper and limonene/terpinene/phellandrene in the form of lime oil? If so, what is the formula of the complex formed? I tried the reaction with lime oil in iPrOH, and a copper sulfate solution. The result was a blue crystalline solid. What are ... |
Can copper sulfate react with terpenes (such as limonene and terpinenes) at room temperature? |
This is a pretty naive question. The probabilistic definition of entropy is (for a mole of particles)
$$-R\sum_i p_i\ln p_i $$ in which $p_i$ is the probability of a given microstate and $\sum p_i =1, p_i\geq 0.$
If we have a large system whose microstates are equally probable the terms of $-R\sum p\ln p$ will tr... |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/NSSYt.png
I believe it is achiral because its mirror image (on the right) is essentially the same molecule. But I was told that it is chiral because it doesn't have an internal plane of symmetry. Could someone tell me which explanation i... |
Is this molecule on the left chiral or achiral? |
The titration curve is a deception of mathematics to our eyes. Look at the y-axis carefully. What do you have on the y-axis? A log function operating on hydrogen ion concentration. A unit change in pH means that hydrogen ions concentration has changed by a factor of 10. As more and more hydroxide ions are removed from ... |
I have read that Boron, due to the very high sum of its first three ionization energies, it is not able to form its +3 ions, and thus it generally forms only covalent compounds.
But in a popular Indian engineering entrance exam: JEE MAINS-2014 19th April paper, this question was asked:
Which of these statements is ... |
Does Boron form any ionic bonds? |
Is this molecule on the left chiral or achiral?
[![1,4‐dibromo‐octahydropentalene][1]][1]
I believe it is achiral because its mirror image (on the right) is essentially the same molecule. But I was told that it is chiral because it doesn't have an internal plane of symmetry. Could someone tell me which explanatio... |
Is (1R,3aR,4S,6aS)‐1,4‐dibromo‐octahydropentalene chiral or achiral? |
>Specific rotation of (+)-2-butanol is 12.5$^{\circ}$ . A sample of 2-butanol containing both the
enantiomers was found to have specific rotation value of –2.8$^{\circ}$ . What is the percentage of (+)-2- butanol in the sample?
I attempted it by letting the percentage of (+)-2-butanol be $x \%$ and therefore percen... |
Let $\ce{HA}$ ($x$ molar) be a strong electrolyte and $\ce{HB}$ ($c$ molar) — weak electrolyte. As $\ce{HA}$ is strong electrolyte, it dissociates completely:
$$
\begin{array}{lcc}
\ce{&HA &-> &H+ &+ &A-} \\
\text{initially} & x && 0 && 0 \\
\text{after} & 0 && x && x
\end{array}
$$
As HB is weak electrolyt... |
I am currently studying *Ultrasonic transducers – Materials and design for sensors, actuators and medical applications* by Kentaro Nakamura. In chapter **1.2.1 Ferroelectricity**, the author says the following:
> $\ce{BaTiO_3}$ is realised as a ceramic, originating as a mouldable paste, which is dried and sintered t... |
What is meant by "basis" in "... its basis in particles leads to a material comprising crystallites or grains tightly bound together, ..."? |
I have read that Boron, due to the very high sum of its first three ionization energies, it is not able to form its +3 ions, and thus it generally forms only covalent compounds. But in a popular Indian engineering entrance exam: JEE MAINS-2014 19th April paper, this question was asked:
> Which of these statements i... |
This is a pretty naive question. The probabilistic definition of entropy is (for a mole of particles)
$$-R\sum_i p_i\ln p_i $$ in which $p_i$ is the probability of a given microstate and $\sum p_i =1, p_i\geq 0.$
If we have a large system whose microstates are equally probable the terms of $-R\sum p\ln p$ will tr... |
In the mechanism for Lucas' Test for Alcohols, I am reading two different types. One says the first step is the abstraction of a proton from HCl, but on other references, I also see that the first step is the formation of a zinc chloride complex. Anyone can clear this out for me? Thanks |
In my class test, I was asked this question:
> Which mechanism would be followed by a certain reaction with good
> leaving group?
>
> 1. E1 reaction
>
> 2. E2 reaction
>
> 3. No reaction
>
> 4. both E1 and E2
I answered 4 because **they both occur simultaneously the main difference comes in the a... |
Which mechanism would be followed by a certain reaction with good leaving group? |
How to calculate/derive the change in entropy of a heat reservoir as function of its internal energy? If the constant temperature of heat reservoir is T, and
$$ S(U_0)=S_0,$$
what is $$ S(U)? $$
|
With this system, it would be possible to have three liquid phases and two liquid-liquid coexistence regions at various compositions. Similar behaviour is common for solids such as alloys, sometimes with even more stable phases.
I have been searching for a liquid mixture with this behaviour, but haven't found any. A... |
Is it possible to have three stable liquid phases in a binary mixture? |
It seems that water does not begin boiling at 100.001 degrees C. A pot of water keeps getting hotter and hotter until it produces $H_2O$ vapor at a rate sufficient to produce a visible bubble in one location, and then turbulence shakes some more vapor free. The extra nucleation sites proposed by Waylander suggests that... |
For a reservoir of finite thermal inertial, the change in entropy is $$MC\ln{(T_f/T_i)}=MC\ln{\left[\frac{(T_i+\frac{Q}{MC})}{T_i}\right]}$$
Here's a hint: What is the limit of this as the thermal inertial of the reservoir MC becomes infinite? |
I have read that boron, due to the very high sum of its first three ionization energies, it is not able to form its +3 ions, and thus it generally forms only covalent compounds. But in a popular Indian engineering entrance exam: JEE MAINS-2014 19th April paper, this question was asked:
> Which of these statements i... |
Does boron form compounds without covalent bonds? |
I had to identify the structure of a drug based off the spectra I had. I suck at this. I gave it my best go and got some ugly structure, only to check it using a database and find out I was wrong. I gave up and searched for the chemical structure I was given, only to find out that the drug was diazepam and I was on the... |
I had to identify the structure of a drug based off the spectra I had. I suck at this. I gave it my best go and got some ugly structure, only to check it using a database and find out I was wrong. I gave up and searched for the chemical structure I was given, only to find out that the drug was diazepam and I was on the... |
We do know that the concentration of a catalyst might affect the rate of reaction; but if the catalyst is included in the rate law? For example, $\ce{O3 +M <=>[$k_1$][$k_{-1}$] O2 + O + M}$, where M is obviously a catalyst, when I am writing the rate change of O, do I write $$\dfrac{d[\ce{O2}]}{dt}=k_1 [\ce{O3}][\ce{M}... |
What is a common cause of peak tailing?
a. The distribution constant decreases as analyte concentration increases.
b. The distribution constant increases as analyte concentration increases.
c. The plate height increases as analyte concentration increases.
d. The plate height decreases as analyte concentrati... |
What is a common cause of peak tailing? |
Came across a few graphs that represent the mutual solubility of two compounds, for eg, solubility of KCl, and NaCl with H2O.
On these particular graphs, I can see Y axis as gms/100ml of KCl, on X axis it has gms/100ml of NaCL, and the graph has multiple lines each representing a curve at a specific temprature.
... |
How to read mutual solubility curves? |
I came across several examples of hydrocarbons having resonance that also seem to have a sharp odour. So, does resonance have an effect on smell? |
Is there any relation between resonance and smell of a hydrocarbon? |
How to calculate ∆rGº from entropy and ∆fGº in different temperatures? |
[![enter image description here][1]][1]
In solid, energy bands means the 1s orbital with spin up and down become 3 states when there are 3 atoms.
But then. If you look at hydrogen atoms, the allowed bound states have energies equal to En=Ry/(n2) and n is the main quantum number ranging from 1 to infinity. In ot... |
Question to find increment in total energy of a sample of He gas? |
When dealing with determining the ground state energy of a system, people often say that it is better to know the energy difference rather than the absolute minimum energy. I understand that the absolute minimum energy depend on the model so the more complex your model, the lower or closer the energy you found to the t... |
We do know that the concentration of a catalyst might affect the rate of reaction. But what if the catalyst is included in the rate law? For example,
$$\ce{O3 + M <=>[$k_1$][$k_{-1}$] O2 + O + M},$$
where $\ce{M}$ is the catalyst, when I am writing the rate change of $\ce{O},$ do I write
$$\frac{\mathrm d[\ce{... |
>lithium chloride is considered to be an ionic compound,but it is soluble in alcohol,which suggests that it also posses a small amount of covalent character.
This is an extract from my book ,when I looked it up it said ionic bonds are soluble in water .
So how does lithium chloride's solubility in alcohol prove i... |
Are covalent compounds soluble in water? |
The difference between bands in liquids and solids is the difference between [homogeneous and inhomogeneous broadening][1]. In both cases you get bands (a distribution of energies), but in one case it is because of coupling between different atoms/molecules whereas in the latter it is because of variations in the local... |
The difference between bands in liquids and solids is the difference between [homogeneous and inhomogeneous broadening][1]. In both cases you get bands (a distribution of energies), but in one case it is because of resonant coupling between different atoms/molecules whereas in the latter it is because of variations in ... |
I had to identify the structure of a drug based off the spectra I had. I suck at this. I gave it my best go and got some ugly structure, only to check it using a database and find out I was wrong. I gave up and searched for the chemical structure I was given, only to find out that the drug was diazepam and I was on the... |
We do know that the concentration of a catalyst might affect the rate of reaction. But what if the catalyst is included in the rate law? For example,
$$\ce{O3 + M <=>[$k_1$][$k_{-1}$] O2 + O + M},\tag{1}$$
where $\ce{M}$ is the catalyst, when I am writing the rate change of $\ce{O},$ do I write
$$\frac{\mathrm... |
This is a pretty naive question. The probabilistic definition of entropy is (for a mole of particles)
$$-R\sum_i p_i\ln p_i $$ in which $p_i$ is the probability of a given microstate and $\sum p_i =1, p_i\geq 0.$
If we have a large system whose microstates are equally probable the terms of $-R\sum p\ln p$ will tr... |
is it possible to say that:
H+ is used due to the provision of an acidic medium
H2O used as it is an aqueous medium and products have oxygen, so logically oxygen must come from H2O?
electrons added to conserve charge
? |
What is the purpose of balancing a redox half equation using H+ and H2O and electrons? |
is it possible to say that:
1) H+ is used due to the provision of an acidic medium
2) H2O used as it is an aqueous medium and products have oxygen, so logically oxygen must come from H2O?
3) electrons added to conserve charge? |
This is a pretty naive question. The probabilistic definition of entropy is (for a mole of particles)
$$-R\sum_i p_i\ln p_i $$ in which $p_i$ is the probability of a given microstate and $\sum p_i =1, p_i\geq 0.$
If we have a large system whose microstates are equally probable the terms of $-R\sum p\ln p$ will tr... |
Is it possible to say that:
1. H+ is used due to the provision of an acidic medium?
2. H2O used as it is an aqueous medium and products have oxygen, so logically oxygen must come from H2O?
3. Electrons added to conserve charge? |
For my project on Fluorescence, I'm trying to simplify the equation for the Forster distance (I obtained this from the Lakowicz book). To keep track, the units are in square brackets.
$$R_0 = \left(\frac{9000\kappa^2\Phi_D\ln(10)}{128\pi^5N_An^4}J(\lambda)\right)^{1/6} \approx 0.211 (\kappa^2n^{-4}\Phi_DJ(\lambda))^... |
My teacher explained that free radicals could have a geometry that is planar or pyramidal(tending to tetrahedral) based on whether or not it is substituted by lone-pair containing atoms.
For example,
(CH3)3C would exhibit sp2 hybrid geometry of planar.
But when tri-substituted with Flourine/Chlorine, it will exh... |
What is the geometry of a tri-substituted methyl free radical? |
For my project on Fluorescence, I'm trying to simplify the equation for the Forster distance (I obtained this from the Lakowicz book). To keep track, the units are in square brackets.
$$R_0 = \left(\frac{9000\kappa^2\Phi_D\ln(10)}{128\pi^5N_An^4}J(\lambda)\right)^{1/6} \approx 0.211 (\kappa^2n^{-4}\Phi_DJ(\lambda))^... |
Q The potential energy of an electron in the hydrogen atom is-6.8ev.Indicate the excited stage in which electron is present.
Total energy would be equal to -3.4eV
I used the formula
-13.6 ($\frac{1}{1^2} - \frac{1}{n^2}$= -3.4 eV
n^2 - 1/ n^2 = 4.
I got answer as $3n^2$ = 4
Which is obviously not correct.Where a... |
I'm student in South Korean.
I have a simple question of Physical Chemistry, but I don't know the answer.
Please help me...
We can find collision cross-section(σ) through experiments in three ways.
first, diffusion flux experiment. diffusion coefficient D = (1/3)x(vλ) = (1/3)x(8RT/πM)x(RT/PNσ). So, σ can be fo... |
I have a simple question of Physical Chemistry, but I don't know the answer.
We can find collision cross-section(σ) through experiments in three ways.
first, diffusion flux experiment. diffusion coefficient D = (1/3)x(vλ) = (1/3)x(8RT/πM)x(RT/PNσ). So, σ can be found by measuring the diffusion flux.
Second, T... |
How is this UV-visible spectra interpreted? |
> The potential energy of an electron in the hydrogen atom is $\pu{-6.8 eV}.$ Indicate the excited stage in which electron is present.
Total energy would be equal to $\pu{-3.4 eV}.$
I used the formula
$$-13.6\left(\frac{1}{1^2} - \frac{1}{n^2}\right) = \pu{-3.4 eV};$$
$$n^2 - 1/ n^2 = 4.$$
I got answer as... |
How is the UV-visible spectra of carbonatotetraamminecobalt(III) nitrate interpreted? |
The difference between bands in liquids and solids is the difference between [homogeneous and inhomogeneous broadening][1]. In both cases you get bands (a distribution of energies), but in one case it is because of resonant coupling between different atoms/molecules whereas in the latter it is because of variations in ... |
The difference between bands in liquids and solids is like the difference between [homogeneous and inhomogeneous broadening][1]. In both cases you get bands (a distribution of energies), but in one case it is because of resonant matching of orbitals between different atoms/molecules whereas in the latter it is because ... |
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