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Membrane pores and transporters see millions of ions flow through them per second. This creates a current and therefore a magnetic field. Do cells have any use for these fields (like maybe drawing charged receptors together?) or is it physiologically irrelevant? |
Do magnetic fields generated from ion flow through a membrane channel have any physiological relevance? |
I got values of $5.0 \times 10^{-4}$, $2.5 \times 10^{-4}$, and $183$ for the following problems. However, these seem to be inaccurate and I'm not sure what to do.
Here is the procedure:
Obtain 6 disposable test tubes. Label the test tubes 1 through 6. To each of the $\pu{6 mm}$ test tubes, add $\pu{5.0 mL}$ of $... |
Assume the Henry’s coefficient for water at 20 C is 1.6∗108 Pa. What is the mole fraction of CO2 that will be dissolved in water assuming that it is at equilibrium with a flue gas containing 0.11 mole fraction CO2 at atmospheric pressure (105 Pa)?
My understanding is that we can use Henry's Law yi∗p=xi∗H (where H is... |
[![g][1]][1]
[1]: https://i.stack.imgur.com/PejlY.png
I can see that in the 1st case, resonance would occur, and in the second case, there would be no resonance effect. I have read the fact that resonance reduces bond length due to partial double bond character.
According to that, shouldn't the C-O bond length ... |
[![1: cyclohex‐2‐en‐1‐one; 2: cyclohex‐3‐en‐1‐one][1]][1]
I can see that in the first case a resonance would occur, and in the second case, there would be no resonance effect. I have read the fact that resonance reduces bond length due to partial double bond character.
According to that, shouldn't the $\ce{C=O}$... |
> Assume the Henry’s coefficient for water at $\pu{20 °C}$ is $\pu{1.6E8 Pa}.$ What is the mole fraction of $\ce{CO2}$ that will be dissolved in water assuming that it is at equilibrium with a flue gas containing $0.11$ mole fraction $\ce{CO2}$ at atmospheric pressure $(\pu{10^5 Pa})?$
My understanding is that we ca... |
I got values of $\pu{5.0E-4}$, $\pu{2.5E-4}$, and $183$ for the following problems. However, these seem to be inaccurate and I'm not sure what to do.
Here is the procedure:
> Obtain 6 disposable test tubes. Label the test tubes 1 through 6. To each of the $\pu{6 mm}$ test tubes, add $\pu{5.0 mL}$ of $\pu{2.0E–4 M... |
I'm currently doing an IB chemistry individual investigation on the effect of adding bleach to water on the water's dissolved oxygen content. I've used Winkler's method for this and I'm just wondering whether it is possible to do Winkler's method without the presence of iodide ions $(\ce{I-})$, i.e. without adding chem... |
[![Cases][1]][1]
[1]: https://i.stack.imgur.com/YV5WH.png
In cases **1**, **2**, **3**, the compounds will resonate, thus giving them more stability.
Firstly, **I want to know whether N has a +M effect**? (due to it having a lone pair of electrons...?).
In case **1,** resonance occurs and the electron... |
I was going through my chemistry textbook (IB Pearson), and it explicitly stated that the higher the absolute difference between the electronegativity of elements in a binary compound, the more 'ionic' that compound is, which does make intuitive sense given that a higher electronegativity difference leads to the compou... |
[![1: pyridin‐4‐amine; 2: pyridin‐3‐amine; 3: aniline; 4: 1,4,5,6‐tetrahydropyrimidine][1]][1]
In cases **1**, **2**, **3**, the compounds will resonate, thus giving them more stability.
Firstly, **I want to know whether nitrogen has a +M effect**? (due to it having a lone pair of electrons?)
In case **1**, r... |
Safe in context of chemistry, physiology or long term health care prevention ?
With zero knowledge, it is safer to stay with commercial products, until you know, what you are doing.
For mouthwash, calcium carbonate is quite ineffective, being insoluble solid. Better would be solution of sodium bicarbonate ( baking s... |
My question is: what is the best way to extract micro RNA (miRNA) from humans plasma? Whether trizol is suitable, or should I use commercial kits? Thanks |
I was going through my chemistry textbook (IB Pearson), and it explicitly stated that the higher the absolute difference between the electronegativity of elements in a binary compound, the more 'ionic' that compound is, which does make intuitive sense given that a higher electronegativity difference leads to the compou... |
This question might be too common, but I'm very curious to understand and find out if this is possible.
We see a lot of sci-fi movies and TV series where they have plasma guns, in reality is this something achievable ?
I'm very familiar with the concept of "anything is possible", but I have no idea about chemistr... |
Can you achieve plasma charge? |
The change from the liquid state of water to the water vapor requires a large latent heat to loosen the hydrogen bonds. The process of transpiration in the plant involves exactly this change of state. Here, the water evaporates from the lower leaf surface and the leaf gives up some of its heat. In this way, the lead is... |
In the laboratory notes it is indicated that it is ill advised to eat the solid formed from this experiment. An esterification reaction, in which salicylic acid is treated with acetic anhydride.
If it is for the acid added as catalyst either sulfuric acid or phosphoric acid. Why isn't it possible to neutralize it wi... |
Is chirality a property of only molecules with exactly 1 chiral centre? |
How can you calculate the pH if you know for example the $pK_a$ or $pK_b$ value of a weak acid/base and how much acid/base can dilute in water. Let's take an example:
Quinoline has $pK_a = 4,5$ and $0,6\ \mathrm{g}/100\ \mathrm{ml}$ can dilute in water. I can easily calculate that the concentration of the saturated ... |
How can you calculate the $\mathrm{pH}$ if you know for example the $\mathrm{p}K_\mathrm{a}$ or $\mathrm{p}K_\mathrm{b}$ value of a weak acid/base and how much acid/base can dilute in water. Let's take an example:
Quinoline has $\mathrm{p}K_\mathrm{a} = 4.5$ and $\pu{0.6 g}/\pu{100 ml}$ can dilute in water. I can ea... |
Is the distance of some $n^{th}$ shell ($n$ $\neq$ outermost shell) from the nucleus of an atom different for different elements?
If so, then how much is the difference or how could we calculate it? |
### Setup
Consider a closed binary mixture of known total molar composition $n_i$, held at volume $V$ and temperature $T$. The equilibrium phase composition is determined by $\mu_i^{vap} = \mu_i^{liq}$. Assume the vapor is an ideal gas mixture, the liquid is an [ideal mixture](https://en.wikipedia.org/wiki/Ideal_so... |
By "plasma charge", do you mean to transfer electric charge with a plasma?? If so, then certainly, a plasma can transfer charge.
Plasma guns are commonly used to reduce static charge, e.g. when pulling plastic from a roll or [cleaning dust from vinyl discs][1]. Small ones are available from [about US$100][2] and [l... |
A plasma discharge certainly can transfer charge.
Plasma guns are commonly used to reduce static charge, e.g. when pulling plastic wrap from a roll or [for cleaning dust from vinyl discs][1]. Small ones are available from [about US$100][2] and [larger plasma guns for more][3].
Or you could make your own plasma g... |
A better answer starts by being more precise in the type of magnetic field (static for example) and magnitude of exposure.
I have conducted one small crude experiment employing a 'Magnetizer', which is encased in plastic, which is reputedly claimed to produce an ordered collection of strong and weak fields to leave ... |
A better answer starts by being more precise in the type of magnetic field (static for example) and magnitude of exposure.
I have conducted one small crude experiment employing a 'Magnetizer', which is encased in plastic, which is reputedly claimed to produce an ordered collection of strong and weak fields to leave ... |
I just watched a movie about the Apollo missions. They wanted an oxygen/nitrogen atmosphere on the spacecraft. But they said it would be too heavy and expensive to use an oxygen tank and a nitrogen tank and also equipment to monitor and control the mix ratio, so they went with pure oxygen. Why couldn't they put oxygen ... |
Why can't you have compressed oxygen and nitrogen in the same tank? |
A better answer starts by being more precise in the type of magnetic field (static for example) and magnitude of exposure.
I have conducted one small crude experiment employing a 'Magnetizer', which is encased in plastic, which is reputedly claimed to produce an ordered collection of strong and weak fields to leave... |
A better answer starts by being more precise in the type of magnetic field (static for example) and magnitude of exposure.
I have conducted one small crude experiment employing a 'Magnetizer', which is encased in plastic, which is reputedly claimed to produce an ordered collection of strong and weak fields to leave... |
I am relatively new and interested in the field of theoretical chemistry.
I just stumpled across the Klopman - Salem equation (https://en.wikipedia.org/wiki/Klopman-Salem_equation).
In daily life, I only use DFT for bonding energies and I also do not find too many papers about the Klopman - Salem equation, why? (... |
What happened to the Klopman - Salem equation? |
I am looking for a free, very simple tool for IUPAC names of organic molecules.
I teach high school chemistry, and it would be fantastic to have an app or web tool that students could use to draw molecules and verify the systematic names of branched alkanes and simple alcohols, aldehydes, ketones, possibly acids; si... |
Is there a free, super simple app or website for IUPAC names from structures? |
I want to ask a question about the symmetry for $\pi$ orbitals.
We were learning today about the deduction of an MO diagram for a typical $\ce{M-M}$ system with $\ce{D_{\infty h}}$ and I was confused on the labelling of the $\pi$ orbitals.
When labelling the $\ce{dz^2}$ orbitals, the following checklist was pro... |
I just watched a movie about the Apollo missions. They wanted an oxygen/nitrogen atmosphere on the spacecraft. But they said it would be too heavy and expensive to use an oxygen tank and a nitrogen tank and also equipment to monitor and control the mix ratio, so they went with pure oxygen. Why couldn't they put oxygen ... |
Would an alternating electric field cause net motion of ions in a liquid in the case of the electrodes being placed outside the liquid?
Generally speaking, what happens if you apply an external electric field to an ionic liquid, taking into account that there are no electrodes places inside the liquid itself, but ar... |
Is there an uncertainty associated with the value 0 K for absolute zero? |
We're going over quantum basics in chemistry right now and I'm very confused.
Electrons can only accept in discreet quanta to move up an energy level, right? And they reflect other forms of light that don't supply energy in their specific quanta, right? And flame is just infrared electromagnetic radiation, right?
T... |
Why does heating an atom make it emit certain frequencies? |
A better answer starts by being more precise in the type of magnetic field (static for example) and magnitude of exposure.
I have conducted one small crude experiment employing a 'Magnetizer', which is encased in plastic, which is reputedly claimed to produce an ordered collection of strong and weak fields to leave... |
A better answer starts by being more precise in the type of magnetic field (static for example) and magnitude of exposure.
I have conducted one small crude experiment employing a 'Magnetizer', which is encased in plastic, which is reputedly claimed to produce an ordered collection of strong and weak fields to leave... |
When I say absolute zero, I’m not talking about the hypothetical temperature 0 K; I’m talking about the temperature at which a thermodynamic system has the lowest energy.
Everywhere I look, sites maintain that this should be –273.15 ºC, but I can’t find any uncertainty quoted with this prediction. Could someone shed... |
When I say absolute zero, I’m not talking about the hypothetical temperature 0 K; I’m talking about the temperature at which a thermodynamic system has the lowest energy.
Everywhere I look, sites maintain that this should be –273.15 ºC, but I can’t find any uncertainty quoted with this prediction. Could someone shed... |
When I say absolute zero, I’m not talking about the hypothetical temperature 0 K; I’m talking about the temperature at which a thermodynamic system has the lowest energy.
Everywhere I look, sites maintain that this should be –273.15 ºC, but I can’t find any uncertainty quoted with this prediction. Could someone shed... |
[![enter image description here][1]][1]
I've been trying this reaction in my lab and there is the formation of the substituted ethylene diamine but along with that, I am obtaining some amount of RCH2N(CH3)2. The reaction is done under solvent-free condition using only excess of ethylenediamine. After the reaction,... |
How to increase the conversion of a reaction between an ammonium salt and ethylenediamine? |
As another answer explains, absolute zero is used to define our temperature scale, so in a sense it has no uncertainty. But this is not the entire story, as all measurements have uncertainty, and every measurement system has uncertainties associated with it. See e.g. the wikipedia article on the [International Temperat... |
As another answer explains, absolute zero is used to define our temperature scale, so it is precise. But this is not the entire story, as all measurements have uncertainty, and every measurement system has uncertainties associated with it. See e.g. the wikipedia article on the [International Temperature Scale of 1990][... |
Absorbing photons is just one of ways atoms and their electrons, or molecules, can gain energy. Other ways are e.g mechanical collisions and chemical reactions.
Note that atoms do not reflect light they do not absorb, but let it pass through like if they were not there. If they had reflected it, air would have been a... |
As another answer explains, absolute zero is set in the definition of the Kelvin temperature scale as exactly 0 K, so it is precise. But this is not the entire story, as all measurements have uncertainty, and every measurement system has uncertainties associated with it. See e.g. the wikipedia article on the [Internati... |
As another answer explains, absolute zero is set in the definition of the Kelvin temperature scale as exactly 0 K, so it is precise. But this is not the entire story, as all measurements have uncertainty, and every measurement system has uncertainties associated with it. See e.g. the wikipedia article on the [Internati... |
If you want to define your own temperature scale you need at least to fixed (no uncertainty) points. Celcius assigned 0 degrees to a mixture of ice and water at atmospheric pressure and 100 degrees to the boiling point of water. If I understand your question correctly you are asking how can one put a "thermometer" at a... |
I'd like to be able to split the NMR value in Gaussian16 into its diamagnetic and paramagnetic terms. I'm coming over from ADF, where this can be done easily. Is there a straightforward command to give Gaussian16?
Thanks! |
Is there a way to extract the diamagnetic and paramagentic components from NMR output from Gaussian16? |
An Oxidizing agent pulls the electron cloud of the substance being oxidized towards itself, for example:
$$\ce{F2 + 2 X- → 2F^- + X2}\qquad (\ce{X} = \ce{Cl}, \ce{Br}, \ce{I})$$
We also know that Fluorine has very high charge/mass ratio as it is very small in size,
its electron gain enthalpy is very high.
... |
As another answer explains, absolute zero is defined in the Kelvin temperature scale as precisely $\pu{0 K}$. But this is not the entire story, as all measurements have an associated uncertainty (all thermometers are imprecise), see e.g. the wikipedia article describing the [International Temperature Scale of 1990][1] ... |
In general, you can expect an epichlorohydrin to be attacked nucleophilically only on the outer epoxide carbon. First, let me present the synthetic argument: In their total synthesis of RK-397, Burova and McDonald used epichlorohydrin as the starting point for the synthesis of their C10–C16 fragment. The fragment synth... |
[![][1]][1]
[1]: https://i.stack.imgur.com/DRIZJ.png
So I know that KMnO4 converts any side chain irrespective of chain length to -COOH group and Sodalime converts that into the respective alkane. But in Benzyl chloride, the alkyl group side chain also has a chlorine atom attached. How would the mechanism proceed... |
Absorbing photons is just one of ways atoms and their electrons, or molecules, can gain energy. Other ways are e.g mechanical collisions and chemical reactions.
Note that atoms do not reflect light they do not absorb, but let it pass through like if they were not there. If they had reflected it, air would have been a... |
we just had an lab experiment on galvanic cells and we used 0.5M and 1 M Iron(III) nitrate solution at the anode (Iron electrode) and 1M and 0.5 copper(II) nitrate solution at the cathode (copper electrode) for runs 1 and 2 respectively.
My question is how can I determine which redox reaction occurred? There are man... |
How to know which reduction and oxidation reactions occurred? |
We just had a lab experiment on galvanic cells and we used 0.5 M and 1 M iron(III) nitrate solution at the anode (iron electrode) and 1 M and 0.5 M copper(II) nitrate solution at the cathode (copper electrode) for runs 1 and 2, respectively.
How can I determine which redox reaction occurred? There are many possible ... |
When explaining the mathematics behind calculating molecular orbital energy , namely HOMO and LUMO energies, using quantum chemistry, [Chainer Chemistry documentation](https://chainer-chemistry.readthedocs.io/en/latest/tutorial.html#homo-prediction-by-nfp) states that
> From mathematical viewpoint it requires a sol... |
[![][1]][1]
[1]: https://i.stack.imgur.com/DRIZJ.png
So I know that $\ce{KMnO4}$ converts any side chain irrespective of chain length to -$\ce{COOH}$ group and Soda lime converts that into the respective alkane. But in benzyl chloride, the alkyl group side chain also has a chlorine atom attached. How would the ... |
[![re][1]][1]
[1]: https://i.stack.imgur.com/YL80s.png
So I looked it up on the internet and it says that this is to be a nitration reaction. But how is the $\ce{NO2+}$ formed? I simply cant seem to be able to do the first step of the mechanism, that is the generation of the electrophile.
I thought that a... |
Relation between the oxidation state of central atom and its coordination number in a complex compound? |
Question 2b:
> [![![\]\[1\]\]\[1\]][1]][1]
Because of the first peak being large, I think it's either an ester or carboxylic acid. Since there are some carbons not being shown, I figure there is probably some symmetry going on. Since it's kind of hard to make a symmetric ester, I settled on the molecule: methylpr... |
Analytical Organic Chemistry - Do you agree with my answer to this C-13 NMR question? |
I need to heat a fluid for seven days at a time. The fluid goes in round bottom flask that is suspended in a water bath. The test fluid will decompose and generate a small amount of gas over time.
Gas generation is variable and dependent on what material I am testing in this material compatibility experiment.
I h... |
Will ground glass joints relieve pressure non-catastrophically? |
Question 2b:
> [![![\]\[1\]\]\[1\]][1]][1]
Because of the 184.7 signal, I think it's either an ester or carboxylic acid. There isn't a DEPT signal based on 184.7 because the carbon is not bonded to any hydrogens. Since there are some carbons not being shown, I figure there is probably some symmetry going on. From... |
Context: I want to be able to hash real-world objects
Is it possible to create a substance containing a combination of elements (or isotopes?) in a random and difficult to reproduce (but simple to verify) combination?
For example if the "fingerprint" was 69% X and 31% Y this information can be easily hashed but i... |
Is it possible to create an arbitrary, stable, unique chemical fingerprint? |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/jxtol.png
In this MO diagram, we find that the LGOs of the two premixed H1s orbitals are significantly higher in energy than oxygen's 2s orbital. Although oxygen's $Z_{eff}$ is considerably higher, is it really enough to make it so that th... |
If I didn't miss any point, you want to make sure that:
-the system is not in direct contact with the environment, in order to keep it clean
-pressure doesn't build up dangerously
-the non-gaseous product is not lost
What about a reflux condenser? Even unstoppered, it makes loss of material very unlikely. If you are c... |
What would be the comparison between P-F and P-X bond length in compounds $\ce{PF3Cl2}$ and $\ce{PF4Cl}$ in the equitorial hybrid orbital arrangements 
So while determining the bond length between the two compounds I am using bent rule, since in the... |
What would be the comparison between P-F and P-Cl bond length in compounds $\ce{PF3Cl2}$ and $\ce{PF4Cl}$ in the equitorial hybrid orbital arrangements 
So while determining the bond length between the two compounds I am using bent rule, since in th... |
What would be the comparison between $\ce{P-F}$ and $\ce{P-Cl}$ bond length in phosphorus tetrafluoride chloride $\ce{PF4Cl}$ and phosphorus trifluoride dichloride $\ce{PF3Cl2}$ in the equitorial hybrid orbital arrangements?
[![1: PF4Cl; 2: PF3Cl2][1]][1]
While determining the bond length between the two compoun... |
What would be the comparison between $\ce{P-F}$ and $\ce{P-Cl}$ bond length in phosphorus tetrafluoride chloride $\ce{PF4Cl}$ and phosphorus trifluoride dichloride $\ce{PF3Cl2}$ in the equitorial hybrid orbital arrangements?
[![1: PF4Cl; 2: PF3Cl2][1]][1]
While determining the bond length between the two compoun... |
When you ask for a precision of 0.1 ppm, I assume you actually mean the detection limit?
A very common method for quantitative analysis of peroxide content is iodometric titration: the peroxides react with potassium iodide forming free iodine which is subsequently titrated with thiosulfate. It is basically at straig... |
When you ask for a precision of 0.1 ppm, I assume you actually mean the detection limit?
A very common method for quantitative analysis of peroxide content is iodometric titration: the peroxides react with potassium iodide forming free iodine which is subsequently titrated with thiosulfate. It is basically at straig... |
When you ask for a precision of 0.1 ppm, I assume you actually mean the detection limit?
A very common method for quantitative analysis of peroxide content is iodometric titration: the peroxides react with potassium iodide forming free iodine which is subsequently titrated with thiosulfate. It is basically at straig... |
__The Experiment__
A few days ago I saw a video of dissolving gold in the condition of $\ce{ICl3/HCl(aq)}$. In the video, $\ce{ICl3(s)}$ is added to a test tube, followed by adding conc. hydrochloric acid. The solid is dissolved in the solution and the solution turned yellow. No green color was shown.
A gold wire... |
For those who want to convert a few SMILES strings to images, you can also use the CDK 1.5-based Depict utility from John May ([www.simolecule.com/cdkdepict/](https://www.simolecule.com/cdkdepict/), [GitHub](https://github.com/cdk/depict)). It provides various options and outputs Scalable Vector Graphics (which can be ... |
I've been looking at ways to re-concentrate a formic acid-water binary mixture with the VLE diagram below.
[![enter image description here][1]][1]
Am I correct in saying that to concentrate a solution of say , 40% formic acid by weight I could (excluding all recycle streams for simplicity) implement a distillat... |
Azeotropic Distillation - Am I interpreting this VLE diagram correctly? |
Tl, dr -- upon further review we can't really tell whether potassium sulfide or beryllium fluoride is morebionic without some quantitative details.
There is more involved in the balance between ionic and covalent bonding than electronegativity differential. You have to consider molecular orbital structure, too. On... |
Tl, dr -- upon further review we can't really tell whether potassium sulfide or beryllium fluoride is more ionic without some quantitative details.
There is more involved in the balance between ionic and covalent bonding than electronegativity differential. You have to consider molecular orbital structure, too. On... |
Why does only one molecule of secondary amine react with diethyl oxalate and two molecules of primary amine react with diethyl oxalate?
I feel secondary amine also should have reacted similar to primary amine.
From [JEE-Main 2015](https://gradestack.com/JEE-Main-2015-Complete/Nitrogen-Containing/Chemical-Reaction... |
My textbook <!--citation needed--> says that despite the large electronegativity difference $\ce{BeF2}$ is covalent since the beryllium ion will have too much charge density and it will attract the fluorine electron cloud and therefore forms polar covalent bonds.
I looked it up on Wikipedia and found out that it has... |
Is beryllium difluoride covalent or ionic? |
What is the gas that if formed when a reactive metal is placed in a salt solution of a less reactive metal? Theoretically, it should just be a simple displacement.
I know that this question has been asked on a different page, but there Hydrogen formation was the accepted answer, which I don't think is the case (see ... |
Why do bubbles form when a reactive metal is placed in a less reactive metal's salt solution? |
I was just searching around in my store room and I found this Fisher-Price Light Sketcher. I am just amazed how the light from the pen draws on the board without even contact! I searched a lot but couldn't find a working principle of this thing. Probably the light emitted by the pen is black light. Can you tell me how ... |
Background: Glycerin, when heated with a metal coil, decomposes below its boiling point to acrolein, which in turn appears to decompose to formaldehyde and acetaldehyde. ([see previous post][1])
Question: Is there a chemical that could be added, or a process that could be applied, that would lessen the decomposition... |
Like you said, $2 \: doublets$ at around $\pu{7 ppm}$ is belong to *para*-substituted benzene. Three single-proton $multiplets$ around $\pu{5-6 ppm}$ belong probably to a single substituted alkene. A $singlet$ and a $doublet$ between $3$ and $\pu{4 ppm}$ are belong to $\ce{CH3}$- and -$\ce{CH2}$- groups, respectively (... |
The nitrogen oxide NO exists and has an uneven number of valence electrons. This is "impossible". Why does it exist ? Why is it not dimerized ? |
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