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I have seen these small test tube looking doohickeys being supplied from many chinese suppliers, but never with any description as to what they are for. They almost invariably have the description "Automatic Filling Tube Liquid Test Tube With Spout" which didn't lead me anywhere.
With most glassware, even relatively... |
What is the purpose of this glassware? |
*Benzene* and *substituted benzene* (**phenols, aromatic ethers, benzaldehyde, aromatic ketones like acetophenone, benzoic acid, aniline and nitrobenzene**) generally can undergo electrophilic Aromatic substitution reactions.
Now among all of these only benzene and *aromatic ethers* can undergo **Friedel-Crafts alk... |
The crystal structure of tropolone has been determined \[[1](https://doi.org/10.1107/S0567740873002013)\] and is freely available via CCDC (CSD Entry: [TROPOL10](https://www.ccdc.cam.ac.uk/structures/Search?Doi=10.1107%2FS0567740873002013&DatabaseToSearch=Published)).
One can use JSmol on the web page to find the line... |
How can I determine the size of a tropolone molecule?
It's a seven-membered aromatic ring with =O on the first carbon and -OH on the second carbon.
Is there any software available?
[![tropolone][1]][1]
[1]: https://i.stack.imgur.com/R8kHam.png |
How can I determine the size of tropolone molecule? |
The crystal structure of tropolone has been determined \[[1](https://doi.org/10.1107/S0567740873002013)\] and is freely available via CCDC (CSD Entry: [TROPOL10](https://www.ccdc.cam.ac.uk/structures/Search?Doi=10.1107%2FS0567740873002013&DatabaseToSearch=Published)).
One can use JSmol on the web page to find the line... |
I am trying to calculate the density of a magnesium sulphate solution and came across [this](https://pubs.acs.org/doi/pdf/10.1021/je60087a013?casa_token=LbINY_bmAdQAAAAA:K0K3MQODrSnqhwr0xcrQl0Zbk1XokqSR5KI8iSvp4juz9wcWZtM2mfqNmYQeI1u2KENU-5O0GdlJxMs) paper which determines an equation from experiment to do that. Howeve... |
I am trying to calculate the density of a magnesium sulphate solution and came across [this](https://pubs.acs.org/doi/pdf/10.1021/je60087a013?casa_token=LbINY_bmAdQAAAAA:K0K3MQODrSnqhwr0xcrQl0Zbk1XokqSR5KI8iSvp4juz9wcWZtM2mfqNmYQeI1u2KENU-5O0GdlJxMs) paper which determines an equation from experiment to do that. Howeve... |
What is the [enthalpy change of solution][1] of oxygen dissolved into water?
[1]: https://en.wikipedia.org/wiki/Enthalpy_change_of_solution |
What is the enthalpy change of solution of oxygen and water? |
The Sodium emission spectrum has 2 bright yellow lines called the Na-D lines. Superficially I understand the cause; there's spin-orbit coupling and the 3p orbital is split into 3p(3/2) and 3p(1/2).
But I don't understand why those numbers (3/2 and 1/2)?
Are these the total angular momentum values or the orbital a... |
I am trying to calculate the density of a magnesium sulphate solution and came across [this](https://pubs.acs.org/doi/pdf/10.1021/je60087a013?casa_token=LbINY_bmAdQAAAAA:K0K3MQODrSnqhwr0xcrQl0Zbk1XokqSR5KI8iSvp4juz9wcWZtM2mfqNmYQeI1u2KENU-5O0GdlJxMs) paper which determines an equation from experiment to do that. Howeve... |
Why is 1-Ethyl-1-methylcyclohexane achiral? |
I've learnt that pressure is intensive
but I have also learnt that pressure can be added (partial pressures).
which doesn't make sense to me since intensive variables are non-additive.
Where have I flawed in my understanding? |
Is pressure extensive or intensive? |
I did a little thought experiment, where I place an infinitely long beaker filled with some gas, which has a moveable lid at the open part. So if I place this beaker in vaccume, there will obviously be no work done on the system and hence no loss of energy due to the work done by the system (because the int pressure of... |
> Is the computation same and I just need to subtract a molecule of FADH2 per unsaturation (double bond)?
Definitely subtract a molecule of $\ce{FADH2}$. After all, you can skip the first of the the four steps in each cycle of removing two carbons (formation of double bond, adding water across the double bond, oxidi... |
I'm reading about measuring radiation and trying to come up with a more intuitive retelling for an audience familiar with math but not necessarily chemistry or any physical science. Is any or all of the following inaccurate or oversimplified?
- **Radioactivity (Ci, Bq)** - Radiation from the **material's** point of ... |
Is it accurate to describe these radiation measurement units in terms of where-it's-measured and relationship-to-time? |
I'm reading about measuring radiation and trying to come up with a more intuitive retelling for an audience familiar with math but not necessarily chemistry or any physical science. Is any or all of the following inaccurate or oversimplified?
- **Radioactivity (Ci, Bq)** - Radiation from the **material's** point of ... |
Okay so this might seem a bit Weird but the formula for change in enthalpy has been given the following way-
∆H=∆U+∆PV
so in this case when we say ∆V is zero we get that ∆PV is also zero and thus ∆H=∆U. But when we say pressure is constant, my teacher simply takes out the pressure term outside the delta function... |
Why is enthalpy change at constant pressure not only internal energy change? |
Alkene has C-C sigma bonds and C=C pi bonds and also C-H sigma bonds.
I know that C-C and C=C bonds will not give any polarity but what about the C-H bond?
I think it should give some polarity because C is slight more electronegative than H so electrons will slightly go towards C in the C-H bond.
But alkene is... |
The formula for entropy change states that change in entropy is not possible if heat change is nil.
∆S=∆Q/T
But what if we adiabatically expand a gas? Won't the molecules get more space to vibrate in, hence increasing the randomness of the system, therefore increasing the entropy? |
Will entropy increase in adiabatic expansion? |
I've learnt that pressure is an intensive measure,
but I have also learnt that pressure can be added (partial pressures), which doesn't make sense since intensive variables are non-additive.
Where is the flaw in my understanding? |
I did a little thought experiment, where I place an infinitely long beaker filled with some gas, which has a moveable piston at the open part. So if I place this beaker in vaccume, there will obviously be no work done on the system and hence no loss of energy due to the work done by the system (because the int pressure... |
I understand that pure rotational spectra only exist for molecules which have a permanent dipole moment. The common explanation is "so that they can interact with the **E**-field of the incoming photons", but I don't think it is clear why photons can only interact with dipoles.
I'm also aware that the answer probab... |
Why do molecules showing a pure rotational spectra require a permanent dipole? |
We have been told that a symmetry adapted combination of four hydrogen orbitals is used to create localised hydrogen orbitals for methane. These orthonormal combinations are denoted ψa1, ψt’2, ψt’’2 and ψt’’’2.
It then asks to calculate the normalisation constant for the localised orbital Ψ = ψa1 – ψt’2 – ψt’’2 – ψt... |
In a demonstration, aluminum foil was add to a solution of HCl and allowed to react, the reaction was presented as
2Al(s) + 6HCl(aq) --> 2AlCl₃(aq) + 3H₂(g)↑
After filtration, the solution appeared optically clear.
Next, baking soda, i.e. sodium carbonate NaHCO3(s), was added, and the solution then turned w... |
In a demonstration, aluminum foil was add to a solution of $\ce{HCl}$ and allowed to react, the reaction was presented as
$\ce{2Al(s) + 6HCl(aq) -> 2AlCl3(aq) + 3H2(g)↑}$
After filtration, the solution appeared optically clear.
Next, baking soda, i.e. sodium carbonate $\ce{NaHCO3(s)}$, was added, and the so... |
Online answer I found :
The bucket of hot water has more internal energy.
Internal energy depends on the amount (mass) of substance and the kinetic energy of the molecules of the substance.
My thinking to it :
Since it is written dependant on mass, then swimming pool has more mass than bucket of hot water.Since it has... |
Thanks for asking this question. I'd heard before that Pu was actually more chemically toxic than its toxicity due to its radioactivity, but had never followed up by checking out this claim in detail.
**tl;dr**: *Plutonium is very safe unless you grind it up into dust and inhale it, in which case the hazard is proba... |
inside the container is cold water and outside container is hot air.
What I have shown is the microscopic view of container walls(Small part )
A is the surrounding and B is the system or inside the container walls ( Since there is some thickness of container walls and we can say that there are molecules present there... |
How does heat transfer between molecules happen in deep? |
inside the container is cold water and outside container is hot air.
What I have shown is the microscopic view of container walls(Small part )
A is the surrounding and B is the system or inside the container walls ( Since there is some thickness of container walls and we can say that there are molecules present there... |
Are there any sulfides, sulfates, carbonates that cannot be dissolved by aqua regia? |
What is the IUPAC name of this compound? |
inside the container is cold water and outside container is hot water.
What I have shown is the microscopic view of container walls(Small part )
A is the surrounding and B is the microscopic view of container walls ( Since there is some thickness of container walls and we can say that there are molecules present the... |
inside the container is cold water and outside container is hot water.
What I have shown is the microscopic view of container walls(Small part )
A is the surrounding and B is the microscopic view of container walls ( Since there is some thickness of container walls and we can say that there are molecules present the... |
Inside the container is cold water and outside the container is hot water. B is the microscopic view of container walls .W is water
And A is hot water.
What I have shown is the microscopic view of container walls(Small part )
A is the surrounding and B is the microscopic view of the walls of container ( Since ther... |
For a flat, planar molecule, how do you determine which side is up? Or down? |
When papers or articles say that all proteinogenic amino acids are 'levorotatory' or 'L', they often make a point of saying that only half of them are truly, optically levorotatory. All of them (except glycine) are called 'L' because of their 'opposing' configuration to glyceraldehyde, the original molecule deemed to ... |
Are all 'dextrorotatory' sugars in biology actually 'd' or '+' in chirality? |
I am confused as to what suffix to use for the following compound:
[![enter image description here][1]][1]
Should it be carbaldehyde or just -al, like should it be propane-1,2-dicarbaldehyde or should it be propan-1,2-dial?
Or maybe it's 1-methylethane-1,2-dial? I am pretty sure its either of these three or ma... |
If a house had a wooden frame and was caught in a fire, there'd be nothing much left at the end. The damage would be huge. If a house had an iron frame and was caught in a fire, it probably wouldn't be too badly off at the end. Is there a scientific measure of "how things fare in a fire" please? |
Is there a word for "damage done by fire" of a material? |
A1: There is no displacement of the wall, forces are in equilibrium with zero net force.
A2a: If the wall initial temperature was the cold water temperature, then yes. Otherwise no, as the mean kinetic energy of wall molecules can generally goes both ways, depending on initial temperatures of air, wall and water, we... |
A1: There is no displacement of the wall, forces are in equilibrium with zero net force. There are initiated stronger vibrations on Warner Wal side and weaker vibrations on colder wall side.
A2a: If the wall initial temperature was the cold water temperature, then yes. Otherwise no, as the mean kinetic energy of wal... |
A1: There is no displacement of the wall, forces are in equilibrium with zero net force. There are initiated stronger vibrations on warmer wall side by energetic hot air molecules. And weaker vibrations on colder wall side by energy leaching cold water molecules .
A2a: If the wall initial temperature was the cold wa... |
A1: There is no displacement of the wall, forces are in equilibrium with zero net force. There are initiated stronger vibrations on warmer wall side by energetic hot air molecules. And weaker vibrations on colder wall side by energy leaching cold water molecules .
A2a: If the wall initial temperature was the cold wa... |
Simpler explanations, can by their nature be less accurate than a detailed description, but are helpful in beginning to understand things. Getting to the heart of your question:
“How is the aromaticity in graphene different from the aromaticity in benzene? . . . but is it possible to find a simpler if less accurat... |
Alkenes have C–C sigma bonds, C=C pi bonds, and also C–H sigma bonds.
I know that C–C and C=C bonds will not give any polarity, but what about the C–H bond?
I think it should give some polarity because C is slightly more electronegative than H, so the electrons in the C–H bond will be slightly polarised towards C... |
Why are alkenes considered nonpolar? |
I was just wondering. Is there any chemical or historical significance in the fact that 'ethane' is just 'methane' without the 'm'? |
My textbook states: Did you know that if you pour a handful of salt into a glass of water the water level will actually go down rather than overflowing the glass?
I tried this experiment and the glass overflowed.
I did a bit of research online and I think what the writer was referring to is that the volume of the... |
Does the level of water go down when you add salt to it? |
Which has maximum bond energy? F2, N2 or O2? |
When we perform a organic reaction without any addtional catalyst except that the reaction is carried out under microwave condition we can accelerate this reaction in comparison with one under heating only. So, microwaves can be considered a form of catalysis according to the concept of reaction kinetics? |
Given le chatelier principle, there must be a peak pressure of CO2, at which, under room temperature, the reaction of soda with vinegar would stop (Na2CO3+CH3COOH>CO2 + NaCH3COO). Is my reasoning correct and if so what formula to use to calculate it? |
Is it possible to calculate a maximum pressure attainable with a soda vinegar reaction? |
Which of the following octahedral complexes should absorb the photon with the longest wavelength, λ? |
What's the least common element in the universe? And what is its frequency measured in Hertz? |
What's the least common element in the universe? |
Here is an example of an entire online GoolgeBook dedicated to the topic [Microwave Assisted Organic Synthesis](https://www.google.com/books/edition/Microwave_Assisted_Organic_Synthesis/CrfzIiN5qlgC?hl=en&gbpv=1&dq=organic+microwave+assisted+synthesis&pg=PR5&printsec=frontcover), apparently based on some 2,000 papers.
... |
Here is an example of an entire online GoolgeBook dedicated to the topic [Microwave Assisted Organic Synthesis](https://www.google.com/books/edition/Microwave_Assisted_Organic_Synthesis/CrfzIiN5qlgC?hl=en&gbpv=1&dq=organic+microwave+assisted+synthesis&pg=PR5&printsec=frontcover), apparently based on some 2,000 papers.
... |
$$\ce{(i) LiHCO_3 (ii) Ca(HCO_3)_2 (iii) Zn(HCO_3)_2 (iv) AgHCO_3}$$
From my prior knowledge compounds i and ii are not solids because of the high hydration energy of Li and the high polarizing power of Ca respectively. But the answer to this question includes both options iii and iv. Which property ma... |
Which metal bicarbonates do not exist in solid state? |
Given Le Chatelier's principle, there must be a peak pressure of $\ce{CO2}$, at which, under room temperature, the reaction of soda with vinegar would stop?
$$\ce{Na2CO3 + CH3COOH -> CO2 + CH3COONa}$$
Is my reasoning correct and if so what formula to use to calculate it? |
The general equation for liquid junction potential is given by $$E = {-RT\over F}\sum_i\int_a^b{t_i\over z_i}d ln(a_i)$$
Where a and b are the two phases, $t_i$ is the transport number of the ions and $z_i$ is the charge on the ions.
When making the additional assumptions that (1) the concentrations are equivalent to... |
How to derive the Henderson equation for liquid junction potentials given in Bard and Falkner? |
Here is an example of an entire online GoogleBook dedicated to the topic [Microwave Assisted Organic Synthesis](https://www.google.com/books/edition/Microwave_Assisted_Organic_Synthesis/CrfzIiN5qlgC?hl=en&gbpv=1&dq=organic+microwave+assisted+synthesis&pg=PR5&printsec=frontcover), apparently based on some 2,000 papers.
... |
Which of the following octahedral complexes absorbs the photon with the longest wavelength, λ? |
I'm interested in the spectra of gas discharge tubes.
Taking neon as an example, when I look up on NIST the spectra for neon, I find excitation states up to Ne IX. Where do I find/how do I work out which excitation states are predominate in a neon light? Is it voltage- or current-dependent, or depending on transition... |
Given Le Chatelier's principle, there must be a peak pressure of $\ce{CO2}$, at which, under room temperature, the reaction of soda with vinegar would stop?
$$\ce{Na2CO3 + 2 CH3COOH -> CO2 + 2 CH3COONa + H2O}$$
Is my reasoning correct and if so what formula to use to calculate it? |
Is there a chemical or historical significance in the fact that 'ethane' is just 'methane' without the 'm'?
|
Why is '-ethane' in 'methane'? |
> Why was Avogadro's number chosen to be the value that it is?
Your question implies that you already know that it was a choice rather than something derived from first principle. There are some numbers that are derived from first principles. In math, $\pi$ and $e$ are not a choice, but can be derived from their pro... |
Does the volume of water involved affect rate of electrolysis? |
I bought a home generator for making hypochlorous acid by electrolysis of a water and salt solution. I would like to figure out guidelines for safe and effective use of my generator.
I have found multiple resources saying that hypochlorous acid solution is not harmful to people or animals and yet very effective as ... |
I bought a home generator for making hypochlorous acid by electrolysis of a water and salt solution. I would like to figure out guidelines for safe and effective use of my generator.
I have found multiple resources saying that hypochlorous acid solution is not harmful to people or animals and yet very effective as ... |
The following question was given in **chemistry today , August 2020 edition** , page 47 , problem 9. The answer to this problem is (a).
[![enter image description here][1]][1]
**My Attempt**
[![enter image description here][2]][2]
In the third step , the carbon electrophile can attack at ortho position ... |
Is OMethyl group on Benzene meta directing? |
Is a Methoxy group meta directing? |
What is intermolecular distance in water? |
The following question was given in **chemistry today , August 2020 edition** , page 47 , problem 9. The answer to this problem is (a).
[![enter image description here][1]][1]
**My Attempt**
[![enter image description here][2]][2]
In the third step , the carbon electrophile can attack at ortho position ... |
When brass solution (mixed with nitric acid and urea) is to be estimated for amount of copper present, ammonia is added to neutralize the solution. This gives a turbidity which can be dissolve by adding ammonium bifluoride (NH4HF2).
What exactly causes the turbidity? Which compound formation is responsible for the tu... |
Why Ammonium bifluoride is used in the iodometric estimation of copper in brass? |
Here are my comments having extensively studied (pending patents) and produced (albeit not via electrolysis) hypochlorous acid ($\ce{HOCl}$) for various applications.
First, a possible issue I have is the mentioned use of vinegar, an organic acid, to the mix. The reason arises if not employing distilled water (meani... |
Is a Methoxy group meta directing in this problem? |
Here are my comments having extensively studied (pending patents) and produced (albeit not via electrolysis) hypochlorous acid ($\ce{HOCl}$) for various applications.
First, a possible issue I have is the mentioned use of vinegar, an organic acid, to the mix. The reason arises if not employing distilled water (meani... |
Here are my comments having extensively studied (pending patents) and produced (albeit not via electrolysis) hypochlorous acid ($\ce{HOCl}$) for various applications.
First, a possible issue I have is the mentioned use of vinegar, an organic acid, to the mix. The reason arises if not employing distilled water (meani... |
Here are my comments having extensively studied (pending patents) and produced (albeit not via electrolysis) hypochlorous acid ($\ce{HOCl}$) for various applications.
First, a possible issue I have is the mentioned use of vinegar, an organic acid, to the mix. The reason arises if not employing distilled water (meani... |
Here are my comments having extensively studied (pending patents) and produced (albeit not via electrolysis) hypochlorous acid ($\ce{HOCl}$) for various applications.
First, a possible issue I have is the mentioned use of vinegar, an organic acid, to the mix. The reason arises if not employing distilled water (meani... |
Here are my comments having extensively studied (pending patents) and produced (albeit not via electrolysis) hypochlorous acid ($\ce{HOCl}$) for various applications.
First, a possible issue I have is the mentioned use of vinegar, an organic acid, to the mix. The reason arises if not employing distilled water (meani... |
when CuSO4.5H2O is dissolved in water, what physical and chemical effects happens to its water of crystallization?
While solving a stoichiometric problem the ques was that 1litre of CuSO4.5H2O was dissolved in 1 liter water and the concentration of Cu2+ ions were asked. When calculating molarity the volume which those... |
First the backstory:
We've begun growing mushrooms (currently Enoki, Lion's Mane and Blue Oysters if anyone is curious) for the sake of eating and maybe potentially selling someday soon. My partner and I have a combined diplomas and degrees in Biotechnology, so we know about all the rigors of keeping things clean an... |
Here are my comments having extensively studied (pending patents) and produced (albeit not via electrolysis) hypochlorous acid ($\ce{HOCl}$) for various applications.
First, a possible issue I have is the mentioned use of vinegar, an organic acid, to the mix. The reason arises if not employing distilled water (meani... |
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