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I know that you can get rid of the acidity if you just take some baking soda added in water. I learned that these antacids that fizz up also have some citric acid and they react when added in water and produce CO2 along with some other compound.
I like to know the use of citric acid in an antacid. Is it just for the ... |
Are haloalkanes considered a homologous series? For example, when assigning chloromethane to a homologous series, do we say that it belongs to the alkanes or haloalkanes? |
Are haloalkanes considered a homologous series? For example, when assigning chloromethane to a homologous series, do we say that it belongs to the alkanes or haloalkanes?
Edit: I think that it would be a haloalkane. However, I'm unsure if haloalkanes are considered a homologous series. |
Does the photoelectric effect take place if the frequency of the photon is exactly equal to the threshold frequency of the metal? I know the electron is going to be free, but it will have 0 kinetic energy; it will be stationary. If so, can voltage be still created if the metal surface is connected to a positive termina... |
Photoelectric effect with 0 Kinetic Energy? |
I know that you can get rid of the acidity if you just take some baking soda added in water. I learned that these antacids that fizz up also have some citric acid and they react when added in water and produce $\ce{CO2}$ along with some other compound.
I like to know the use of citric acid in an antacid. Is it just f... |
I understand that humans consume *tap water* or *mineral water* which are chemically treated after pumped from natural or artificial reservations.
Sometimes people contaminate these reservations by spitting, pissing and shitting in them (for example, parents hold babies while swimming in a lake)
Pumped water are ... |
Is boiling tap water a must to destroy human mucus, proteins, fats, sugars and nucleic acids it may contain? |
It is usually said that d-orbitals are not usually used in bonding, even for so-called "hypervalent" ones, in compounds that are made purely of main group compounds.
However, after reading an article (or, strictly speaking, the preview of an article) about a calcium complex explicitly involving d-orbital contribution ... |
I understand that humans consume *tap water* which are chemically treated after pumped from natural or artificial reservations.
Sometimes people contaminate these reservations by spitting, pissing and shitting in them (for example, parents hold babies while swimming in a lake)
Pumped water are likely to be filter... |
Is boiling tap water a must to destroy human mucus, proteins, fats, sugars and nucleic acids it may contain? |
Are orthoboric acid and boric acid one and the same thing or we can not write H3BO3 as B(OH)3? |
Does the prefix Ortho have some significance? |
I have to try and work this out using the tetrahedral molecular orbital diagram for [WO4]2- but I am confused as both are d0 right? |
Why is [CrO4]2- coloured but [WO4]2- colourless? |
In our lab, chloroform contains 0.5-1% ethanol to prevent it from producing carbonyl chloride when exposed to UV light.
Question is: will the following reaction success using such chloroform?
![enter image description here](https://wikimedia.org/api/rest_v1/media/math/render/svg/3db7d66b5deb16962e358c9a501ba5db90... |
Produce Carbonyl chloride from "unpure" Chloroform in lab? |
In our lab, chloroform contains 0.5–1% ethanol to prevent it from producing carbonyl chloride when exposed to UV light.
Will the following reaction success using such chloroform?
$$\ce{CHCl3 + H2O2 -> HCl + H2O + COCl2 ^}$$ |
Initially, there is already a product which is a sensor based on Methylene Blue, which can detect changes in oxygen levels in a packaging. However, as our thesis project, we decided to take on this and make it more simple and replicable.
So this is our concern. We decided to try and replicate the "blue bottle exper... |
!!! Can Methylene Blue Detect Spoilage in Food? |
Can Methylene Blue Detect Spoilage in Food? |
In our lab, chloroform contains 0.5–1% ethanol to prevent it from producing carbonyl chloride when exposed to UV light.
Will the following reaction occur using such chloroform?
$$\ce{CHCl3 + H2O2 -> HCl + H2O + COCl2 ^}$$ |
The bond angles of $n > 2$ hydrides are usually around $90^\text{o}$, such as $\ce{PH3, H2S, H2Se, H2Te}$. I understand that this is from increased $p$ character in the bonding with these compounds.
However, for $\ce{SiH4}$ and $\ce{GeH4}$, the bond angles are actually quite close to $109.5^\text{o}$. Why do $\ce{Si... |
Why does SiH4 have unusually large bond angles? |
The bond angles of $n > 2$ hydrides are usually around $90^\circ$, such as $\ce{PH3, H2S},$ $\ce{H2Se},$ $\ce{H2Te}.$ I understand that this is from increased $\mathrm{p}$ character in the bonding with these compounds.
However, for $\ce{SiH4}$ and $\ce{GeH4}$ the bond angles are actually quite close to $109.5^\circ$... |
Are there reactions lead at high temperature at industrial level? |
I am trying to derive the overall rate equation for the photocatalysed halogenation (chlorination) of an alkane that proceed via this 4 step chain reaction:
> $\ce{Cl2->2Cl^. \quad(1) initiation}$
>$\ce{Cl^. +RH->R^. + HCl \quad(2) propagation}$
>$\ce{R^. + Cl2-> RCl + Cl^. \quad(3) propagation}$
>$\ce{R^.... |
I was making coffee with a cup of boiling milk which was 2 days old. I used **instant coffee powder** and some **sugar** for the making of it. Tried to make a very hot coffee but usually prefer medium hotness. When I mixed the hot milk with coffee powder, I immediately observed **coagulation**.
Then, I decided to use a... |
What is the mechanism for the reductive workup of an ozonide using zinc/acetic acid/water? Many sources online show the mechanism using DMS instead:
https://www.khanacademy.org/science/organic-chemistry/alkenes-alkynes/alkene-reactions-tutorial/v/ozonolysis-1
https://www.youtube.com/watch?v=PcO49xCb4Gs |
Is there a plastic that's clear, acetone resistant, and ideally sold in sheet stock that's ~1/8" or 1/4" thick? Both acrylic and polycarbonate are out, they turn cloudy on contact with acetone. I tried a piece of PETG and it was better, but still turned fairly cloudy after a few seconds. I don't need continuous serv... |
I want to ask a question about the exchange integral $\ce{H_{AB}}$ -
If I consider an exchange integral $\ce{H_{AB}}$ the following exchange integral can be evaluated:
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/2mSMP.png
so $\ce{S_{AB}}$ is $0$ at $\ce{R = \infty}$
but in... |
I understand that cyanido is the newly adopted naming in place of cyano but what is cyanato? Can anyone please give examples to illustrate the difference? |
What is the difference between cyanato, cyanido and cyano? When should i use which? |
Are there reactions operated at high temperature at industrial level? |
As far as I get it, we did weight one carbon (12,6-isotope) atom. Then we said that electrons have nearly zero weight & protons weight nearly the same as neutrons. Hence we took the weight of that one atom and divided it by twelve and this way we got the mass of a proton/neutron:
w_{n,p} = 1.6726 \cdot 10^{-24} ... |
How do we weight one C atom? |
As far as I get it, we did weight one carbon (12,6-isotope) atom. Then we said that electrons have nearly zero weight & protons weight nearly the same as neutrons. Hence we took the weight of that one atom and divided it by twelve and this way we got the mass of a proton/neutron:
$w_{n,p} = 1.6726 \cdot 10^{-24} g$... |
Itvturn out this question has some subtleties. The analysis presented below, based on Huckel MO theory, indicates that:
1.
The compound as presented by the OP is not aromatic and would be anti -aromatic bhvtgd Huckel model -- meaning in practice it would probably distort out of full conjugation to avoid this calam... |
It turns out this question has some subtleties. The analysis presented below, based on Huckel MO theory, indicates that:
1.
The compound as presented by the OP is not expected to be aromatic and would be anti-aromatic by the Huckel model -- meaning in practice it would probably distort out of full conjugation to a... |
This is a question worth debating and discussion. First of let us realize the fact that we are used to looking at *relative* atomic weights or masses (if someone wants to be too accurate). No Table lists the *absolute* atomic masses of atoms in the periodic table, i.e., through out the history we have to assumed either... |
This is a question worth debating and discussion. First of let us realize the fact that we are used to looking at *relative* atomic weights or masses (if someone wants to be too accurate). No Table lists the *absolute* atomic masses of atoms in the periodic table, i.e., through out the history we have to assumed either... |
As far as I get it, we did weigh one carbon (12,6-isotope) atom. Then we said that electrons have nearly zero weight & protons weight nearly the same as neutrons. Hence we took the weight of that one atom and divided it by twelve and this way we got the mass of a proton/neutron:
$w_{n,p} = 1.6726 \cdot 10^{-24} g$
... |
How do we weigh one C atom? |
As far as I get it, we did weigh one carbon (12,6-isotope) atom. Then we said that electrons have nearly zero weight and protons weight nearly the same as neutrons. Hence we took the weight of that one atom and divided it by twelve and this way we got the mass of a proton/neutron:
$w_\mathrm {n,p} = 1.6726 \cdot 10... |
I have to try and work this out using the tetrahedral molecular orbital diagram for $\ce{[WO4]^2-}$ but I am confused as both are $\mathrm d^0$ right? |
Why is chromate coloured but tungstate colourless? |
In the book that Wikipedia cites (Advanced Organic Chemistry: Reaction Mechanisms
By Reinhard Bruckner, ISBN 9780080498805), they have a different set of assumptions. They are saying the formation of chlorine radicals proceeds by a fast equilibrium. Then, they say that the organic radical is at steady state, ignoring ... |
I know that anions such as $\ce{CH3COO-}, \ce{OH-}, \ce{CN-}$ are basic in nature, since they are conjugate bases of weak acids. Similarly, cations such as $\ce{NH4+}, \ce{H3O+}$ are acidic in nature , since they conjugate acids of weak bases.
However, we also have another case whereby, anions such as $\ce{HSO3-}, ... |
Do amphoteric cations exist? |
#What is the origin of colours?
Most of the colours that we perceive are originate by the selective absorption of some spectral bands and the reflection of the others wavelength, some times with the contribution of fluorescence from the absorption at a higher wavelength. If we exclude colour due to interference (e.g. ... |
I am performing relaxed scan in Gaussian and I'm trying to understand the optimization output. Specifically, the line ```Optimization completed on the basis of negligible forces```. I understand that these forces are the maximum and RMS forces above.
Some examples of "negligible forces" from my output file:
... |
I know that anions such as $\ce{CH3COO-}, \ce{OH-}, \ce{CN-}$ are basic in nature, since they are conjugate bases of weak acids. Similarly, cations such as $\ce{NH4+}, \ce{H3O+}$ are acidic in nature , since they conjugate acids of weak bases.
However, we also have another case whereby, anions such as $\ce{HSO3-}, ... |
If you compare the diffusion coefficient of hydroxide ($\pu{5.270e9 m^2/s}$) to that of fluoride ($\pu{1.460e9 m^2/s}$), you might be surprised to see such a difference despite their comparable size. The mechanism for the higher diffusion rate are acid/base reactions with neighboring waters. Instead of swapping positio... |
This is actually a lot simpler than I initially thought. I'll be using the same example as previously explained in [How to obtain the radial probability distribution function from a quantum chemical calculation?](https://chemistry.stackexchange.com/q/70021/4945) My test setup has slightly changed since then, i.e. I've ... |
My friend and I were discussing the extremely low energy density of modern batteries and read that food has a much higher energy density. Thus, we were considering the possibility of using biological processes to extract energy from food and use that to create an electric potential or do work in some other way.
The ... |
What is the difference between:
1. Meso compound and an optically inactive compound
2. Chiral compound and an optically active compound
For all examples i have seen, chiral compounds were optically active and meso were optically inactive so is there any difference between them?
|
>[Comment by Poutnik] Important is also [en.wikipedia.org/wiki/Grotthuss_mechanism][1] for the proton interchange. Mobility of H3O+ and OH- gives a hint it must be fast.
If you compare the diffusion coefficient of hydroxide ($\pu{5.270e9 m^2/s}$) to that of fluoride ($\pu{1.460e9 m^2/s}$), you might be surprised to ... |
What is the equivalence of 40 ppt to pg/mL? |
One path I accept is as proceeding via the created presence of HOI from the interaction of iodine and SO2 with water in a series of reactions:
$\ce{I2 + H2O = H+ + I- + HOI}$
$\ce{SO2 + H2O = H+ + HSO3-}$
$\ce{HOI + HSO3- -> H+ + I- + HSO4-}$
However, the reaction could also proceed to some extent via the f... |
One path I accept is as proceeding via the created presence of HOI from the interaction of iodine and SO2 with water in a series of reactions:
$\ce{I2 + H2O = H+ + I- + HOI}$
$\ce{SO2 + H2O = H+ + HSO3-}$
$\ce{HOI + HSO3- -> H+ + I- + HSO4-}$
However, the reaction could also proceed to some extent via the f... |
I know that anions such as $\ce{CH3COO-}, \ce{OH-}, \ce{CN-}$ are basic in nature, since they are conjugate bases of weak acids. Similarly, cations such as $\ce{NH4+}, \ce{H3O+}$ are acidic in nature , since they conjugate acids of weak bases.
However, we also have another case whereby, anions such as $\ce{HSO3-}, ... |
The reduction potential for $\ce{Au^3+ + 3e- -> Au}$ is $1.503 \text{ V}$. The reduction potential of $\ce{Cl2 + 2e- -> 2Cl-}$ is $1.36 \text{ V}$. So, the $E^o$ for $\ce{2Au^3+ + 6Cl- -> 2Au + 3Cl2}$ is $0.143 \text{ V}$.
If the reaction $\ce{2Au^3+ + 6Cl- -> 2Au + 3Cl2}$ has a positive E standard ($E^o$ = $0.143 \... |
How can AuCl3 exist? |
One path I accept is as proceeding via the created presence of HOI from the interaction of iodine and SO2 with water in a series of reactions:
$\ce{I2 + H2O = H+ + I- + HOI}$
$\ce{SO2 + H2O = H+ + HSO3-}$
$\ce{HOI + HSO3- -> H+ + I- + HSO4-}$
However, the reaction could also proceed to some extent via the f... |
[This link][1] has a short paragraph on the very first page, which says: "There are two useful criteria to evaluate the presence and the strength of a H-bond. The first is to look at the distance between the H and the A atom, which should be shorter than the sum of their Van der Waals radii. A second method suggests to... |
*There is a range of elimination reactions with E1cb at one end, E1 at the other end and E2 in between. It is not uncommon for these different reaction pathways to compete with one another. For example, in some elimination reactions, the E1 and E2 pathways can operate in competition with one another. Activation energy ... |
I recently realised that the STO-nG basis functions were fit to 1s/20/3d STOs of various exponents, instead of being fit to STOs of higher principal quantum numbers (such as 2s/3p orbitals etc.).
Has a Gaussian expansion of STOs of higher quantum numbers (for example, 2s or 3p STOs) been performed, and are there a... |
GTOs of higher quantum numbers? |
>Has a Gaussian expansion of STOs of higher quantum numbers (for example, 2s or 3p STOs) been performed
I am unaware of such fitting. Typically, basis sets using higher angular momenta (cc-pV$n$Z, def2-$n$ZVP, pc-$n$) are fitted on total energies or correlation energies. See https://www.basissetexchange.org/ for exa... |
Lewis acidity is a function of electron deficiency on the acceptor atom, which in this case is $\ce{B}$ and $\ce{Al}$ respectively.
Back donation is better as is the case of $\ce{B}$, due to better 2p overlap compared to 3p overlap, then the electron deficiency on the $\ce{B}$ atom should be lesser, as it's deficie... |
*There is a range of elimination reactions with E1cb at one end, E1 at the other end and E2 in between. It is not uncommon for these different reaction pathways to compete with one another. For example, in some elimination reactions, the E1 and E2 pathways can operate in competition with one another. Activation energy ... |
The content of mineralic ions in tap water is usually rather small compared to the amount that you take in with your daily food. Especially Calcium content varies wildly between sources, and nobody recommends calcium supplements in cities with soft, low calcium content water.
The common DI water you have from a tap ... |
> Now, according to wikipedia, NaCl has a lattice energy of −756 kJ/mol.
First, we have to understand the term lattice energy.
Here is the textbook explanation ([Fleming: Physical Chemistry][1]): The lattice energy is the energy required to separate the ions in an ionic lattice so that they are at infinite distance... |
**Lattice energy**
> Now, according to wikipedia, NaCl has a lattice energy of −756 kJ/mol.
First, we have to understand the term lattice energy.
Here is the textbook explanation ([Fleming: Physical Chemistry][1]): The lattice energy is the energy required to separate the ions in an ionic lattice so that they are ... |
> I recently realised that the STO-nG basis functions were fit to 1s/20/3d STOs of various exponents, instead of being fit to STOs of higher principal quantum numbers (such as 2s/3p orbitals etc.).
If I understand what you are saying, this is incorrect (although feel free to clarify if I am not understanding the que... |
I am studying chemistry, and I am learning about chromatography.
But I am confused about how chromatography is used to ‘separate and purify’ substances.
I have learnt about chromatography using chromatography paper, where the spots of solutions travel up the paper, which is dipped in a solvent.
[![Chromatogra... |
How are separated and purified substances obtained from a chromatogram? |
If we have a metal in the gas phase. Suppose let's say aluminium. Aluminium has delocalised electrons. There is Al cation -electron attraction in it. It's easier to visualize Al atomic structure in solid form. But if it's in the gas phase, will delocalised electrons return to the atom itself or there is going to be ele... |
Carbon exists in more than one allotropic forms, and the allotropes have different physical properties due to different arrangement of atoms. I am going to compare their hardness for now.
Below is the structure of graphene:
<img src="https://i.stack.imgur.com/FCTHA.png" width="350">
Source: [Wikipedia articl... |
>There is a range of elimination reactions with E1cb at one end, E1 at the other end and E2 in between. It is not uncommon for these different reaction pathways to compete with one another. For example, in some elimination reactions, the E1 and E2 pathways can operate in competition with one another. Activation energy ... |
I've recently came across this reaction and I am wondering about the mechanism. Could someone please help me? If you could give me the name of the reaction (if it has one) it should also be enough for me
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/8N9d8.png |
Is there a treatment for distilled water to become drinkable? |
A 70% “rubbing” alcohol solution will kill those pesky bacterium usually in ten seconds or less. It will also kill a host of viruses, but not all of them.
For your common household disinfecting, a 70% solution will do the trick. Especially for e. Coli, salmonella, staph, and a few others that would be risk bacteriu... |
I recently realised that the STO-nG basis functions were fit to 1s/2s/3d STOs of various exponents, instead of being fit to STOs of higher principal quantum numbers (such as 2s/3p orbitals etc.).
Has a Gaussian expansion of STOs of higher quantum numbers (for example, 2s or 3p STOs) been performed, and are there a... |
I have read about charcoal being used to clean water before it is then boiled or mixed with a UV light stick. I have some questions about this:
> 1) Does it have to be activated charcoal?
>
> 2) Can I use normal charcoal from any old shop (in the UK) as I assume
> these days everything is synthetic or have added... |
Is this correct way to explain principle of RP-HPLC ?
"It works on the principle of hydrophobic interactions hence the more nonpolar the material is, the longer it will be retained." ? |
What is the principle of RP-HPLC? |
> "It works on the principle of hydrophobic interactions hence the more nonpolar the material is, the longer it will be retained." ?
It is a very crude, first order, approximation. A philosophical then arises, what is "non-polar" material and how would we measure it's nonpolarity? One should immediately start to see... |
Can thiocyanic acid be synthesised by combining equimolar amounts of ammonium hydrosulfide and carbon dioxide in the presence of a strong dehydrating agent (phosphorous pentoxide, conc. sulfuric acid etc) in the following reaction: NH4(SH) + CO2 -> HSCN + 2H2O ? |
Gday,
I only have basic chemistry knowledge (highschool and a bit of exposure to first year undergrad material).
I need some help figuring out what theory and techniques to study so I can work out the following problem:
If I mix sodium fluoride, calcium carbonate powder, and water, under what conditions (if any)... |
Will NaF + CaCO3 precipitate much CaF? |
Can sodium thiocyanate be synthesised by combining equimolar amounts of ammonia, sodium hydrosulfide and carbon dioxide in the presence of a strong dehydrating agent (phosphorous pentoxide, conc. sulfuric acid etc) in the following reaction: NH3 + NaSH + CO2 -> NaSCN + 2H2O ? |
Can sodium thiocyanate be synthesised by combining equimolar amounts of ammonia, sodium hydrosulfide and carbon dioxide in the presence of phosphorous pentoxide by the following reaction: NH3 + NaSH + CO2 -> NaSCN + 2H2O ? |
In a 2-electron atom of lowest energy, the $(1s)^2$ is occupied and the electronic wave-function must satisfy anti-symmetry requirements in the particle coordinates, as the spacial wave function is symmetric. How does this transition for 3 electron atoms?
In a 3-electron atom (or in a nucleon with one excited quark)... |
I only have basic chemistry knowledge (highschool and a bit of exposure to first year undergrad material).
I need some help figuring out what theory and techniques to study so I can work out the following problem:
If I mix sodium fluoride, calcium carbonate powder, and water, under what conditions (if any) would I ... |
Will NaF + CaCO3 precipitate much CaF2? |
Is Aluminium foil pure Aluminium? Or does it have other elements in the e.g: Tin(Sn) or Lead(Pb)? Because when I try to oxidize it through the process of submerging it in water, I doesn't look like it wants to oxidize to Aluminium Oxide(AlO+), I did this exact same thing with pure Aluminium and It Oxidized within minut... |
Is Aluminium foil pure Aluminium? |
In a 2-electron atom at lowest energy, the $(1s)^2$ is occupied and the electronic wave-function must satisfy anti-symmetry requirements in the particle coordinates, as the spatial wave function is symmetric. How is the situation in a 3 electron system?
In a 3-electron atom (or in a nucleon with one excited quark) o... |
My wife recently found some website recommending mixing 91% isopropyl alcohol, white vinegar, water, and corn starch and using it to wipe down countertops. This would be where we put our raw chicken and pork after washing them.
I'm concerned that this won't kill the germs as well as harsh chemicals would, although I... |
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