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Why can oxygen have a coordination number of 3 in a complex between silver and SiO2? |
How can I convert the number of particles per liter to gram per liter? I know the size of these particle and so, I calculated the volume and then by the density I calculate the mass. After that I don't know what to do |
Second law of thermodynamics tells that:
>Energy tends to disperse from being localized if it is not hindered from doing so.
Why does a hot cup of tea become cool? Because the higher vibrational energy of the hot mug & tea was localized only to the tea-mug system. When it is brought in the surroundings, the local... |
How do I visualize an atom? |
I am currently adsorbing proteins to an aluminum hydroxide gel. By adding a carbomer (polymer of acrylic acid cross-linked with allyl sucrose), I achieve a somewhat synergistic formulation. Shortly after adding the carbomer, a granular precipitate forms that adheres to glass. Questions: 1) What is this precipitate?;... |
if I wash chloroform (stabilized with amylene) with sulphuric acid by a separating funnell, where will the chloroform be found (up or bottom)? I think the chloroform will be in the bottom, because it is heavier than sulphuric acid. |
If I wash chloroform (stabilized with amylene) with sulphuric acid in a separating funnel, where will the chloroform be found (top or bottom)? I think the chloroform will be at the bottom, because it is heavier than sulphuric acid. |
I have searched and searched, oh how I have searched. At this point I'm liable to shoot the next person who refers me to individual orbital visualizations.
I am looking for a 3 dimensional visualization of a ***whole*** (moderately complex, hydrogen is just a ball) atom that _includes 3 dimensional orbital geometry_... |
I have searched and searched, oh how I have searched. At this point I'm liable to shoot the next person who refers me to individual orbital visualizations.
I am looking for a 3 dimensional visualization of a ***whole*** (moderately complex, hydrogen is just a ball) atom that _includes 3 dimensional orbital geometry_... |
> I have searched and searched, oh how I have searched.
Do you know what I always tell my mom when she asks me to find something in the Internet she was not able to find herself? I ask her: "Are you sure that the thing you are looking for even exists?"
> I am looking for a 3 dimensional visualization of a whole (... |
> I have searched and searched, oh how I have searched.
Do you know what I always tell my mom when she asks me to find something in the Internet she was not able to find herself? I ask her: "Are you sure that the thing you are looking for even exists?"
> I am looking for a 3 dimensional visualization of a whole (... |
I have recently seen a video of ruthenium on youtube. it says that ruthenium is invulnerable to many acids especially aqua regia. but it gets destroyed to a simple household chemical, bleach. the video did not gave proper explanation about why this happens, it only gave the reaction mechanism. what is the reason for th... |
I have searched and searched, oh how I have searched.
I am looking for a 3 dimensional visualization of a ***whole*** (moderately complex, hydrogen is just a ball) atom that _includes 3 dimensional orbital geometry_. A **proper** layered view of the orbitals.
I am not looking for a 'picture' of an atom (i.e. [te... |
I have recently seen a [video][1] of ruthenium on youtube. It says that ruthenium is invulnerable to many acids, especially aqua regia, but it gets destroyed by a simple household chemical, bleach. The video did not give a proper explanation about why this happens, it only gave the reaction mechanism. What is the reaso... |
I have recently studied superposition of states(also the famous Schrodinger's cat), measurement problem, decoherencre & so. I then read the resonance concept from Atkins' Physical Chemistry where it was written as
>It is the superposition of **wavefunctions** representing different electron distributions in the sam... |
Why are there very few persons & books that still advocates the original Pauling's theory of resonance that uses superposition of wavefunctions? |
Why is the original Pauling's theory of resonance that uses superposition of wavefunctions not used today? |
I have searched and searched, oh how I have searched.
I am looking for a 3 dimensional visualization of a ***whole*** (moderately complex, hydrogen is just a ball) atom that _includes 3 dimensional orbital geometry_. A **proper** layered view of the orbitals.
I am not looking for a 'picture' of an atom (i.e. [te... |
I have searched and searched, oh how I have searched.
I am looking for a 3 dimensional visualization of a whole (moderately complex, hydrogen is just a ball) atom that includes orbital geometry. A proper 'layered' view of the orbitals.
What I am not looking for:
- Individual orbital geometry.
- A 'picture'... |
I was learning about voltaic cells and came across salt bridges. If the purpose of salt bridge is only to move electrons from electrolyte solution to the other, then why can I not use a wire?
Also, will using $\ce{NaCl}$ instead of $\ce{KNO3}$ in making of salt bridge have any effects on voltage/current output of th... |
In my experience, most foods smell as they taste. Fragrant soaps, however, taste quite awful in comparison to their fragrances. How can some things smell and taste identically while others are so vastly different? I have a feeling this may have something to do with the vapor pressures of the molecules that make up the... |
This question is probably a [duplicate](http://chemistry.stackexchange.com/questions/5477/) and [there's another question](http://chemistry.stackexchange.com/questions/2644) related to salt bridges on this site.
The purpose of a salt bridge is **not** to move electrons from the electrolyte, rather to maintain charge... |
I have recently studied superposition of states (also the famous Schrodinger's cat), measurement problem, decoherence & so on. I then read the resonance concept from Atkins' Physical Chemistry where it was written as:
>It is the superposition of **wavefunctions** representing different electron distributions in the ... |
I usually use Gaussian/GaussView and don't have to bother with other programs as I think that GaussView is capable of producing nice orbital/surface pictures like this one of one of uracil's Kohn-Sham-orbitals.![GaussView cube file visualization; uracil LUMO][1]
But when it comes that I have to use other programs th... |
I have searched and searched, oh how I have searched.
I am looking for a 3-dimensional visualization of a whole (i.e., moderately complex; hydrogen is just a ball) atom that includes orbital geometry. A proper "layered" view of the orbitals.
What I am *not* looking for:
- Individual orbital geometry.
- A "p... |
I read that the $\ce{O2}$ molecule is [paramagnetic][1], so I'm wondering: could a strong magnet could pull the $\ce{O2}$ to one part of a room – enough to cause breathing problems for the organisms in the room?
(I'm not a professional chemist, though I took some college chemistry.)
[1]: https://en.wikipedia... |
Could a magnet pull oxygen out of the air? |
> So how exactly are these flavonoids shielding UV radiation?
Due to the structure of the flavonoids, there are many transitions to absorb the UV radiation. Also, there are many transitions to release the energy. Most of the time, it is released in 2 steps (2 photons) which equal the energy of the photon that exited... |
I have a beaten old R/C car that I am restoring for my son. It has some nice rubber tires on it, but they are kind of old and worn. The rubber itself is almost moldy and looks matte.
I could just fetch some wonderful product of a shelf somewhere that promises to restore the rubber, but I would like to really know wh... |
What chemicals could be used to repair rubber tires? |
The other answers here have already given good responses to how you would find the answer to the specific example you gave. I want to focus on the question and this particular quote:
> ...it seems unreasonable to know the formula of every compound in
> existence.
You're absolutely right. In principle, we're sup... |
What's with the 70% ethanol? |
Why do we insert a numeric multiplier after group positions when naming an isomer? |
> Have a dissolution of $\ce{HNO_3}$ in water. The density is
> $1.42\ce{g/mL}$ with a concentration of $\ce{16M}$. What is the
> concentration in % mass/mass?
Alright. So the % mass/mass is expressed as
$$\frac{\text{grams of } \ce{HNO_3}}{\text{grams of the dissolution}}\cdot100$$
So I need to find the gra... |
I read that the $\ce{O2}$ molecule is [paramagnetic][1], so I'm wondering: could a strong magnet pull the $\ce{O2}$ to one part of a room – enough to cause breathing problems for the organisms in the room?
(I'm not a professional chemist, though I took some college chemistry.)
[1]: https://en.wikipedia.org/w... |
> You have a mixture of $\ce{He, Ne, Ar}$ gases with a total pressure of
> $8.40$ atmospheres. $\ce{He}$ has a pressure of $1.50$ and $\ce{Ne}$
> has $2.00$. What is the molar fraction of $\ce{Ar}$?
The molar fraction is
$$\frac{\text{moles of Ar}}{\text{total moles of mixture}}$$
However, to know the number... |
It's very difficult to get accurate information concerning the bleach effect. Some sources say it totally "vanished" leaving water + oxygen, some other says it leave some toxic residues (such as sodium hydroxide used to slow its decomposition).
If it does leave toxic residue that need to be neutralized could we use ... |
Will vinegar or baking soda neutralize chlorine bleach? |
It's very difficult to get accurate information concerning the bleach effect. Some sources say it totally "vanished" leaving water + oxygen, some other says it leave some toxic residues (such as sodium hydroxide used to slow its decomposition).
If it does leave toxic residue that need to be neutralized could we use ... |
Is there a compound that **absorbs** all **visible light**? |
How can one get 3,4-dimethylhex-3-ene from but-2-ene ?
![enter image description here][1]
![enter image description here][2]
Using $Br_2$ then two equivalents of $CH_3CH_2MgBr$, I can get the corresponding alkane (3,4-dimethylhexane) but I don't see how to do it while preserving the double bond...
[1]: ... |
How can one get 3,4-dimethylhex-3-ene from but-2-ene ?
![enter image description here][1]
![enter image description here][2]
Using $\ce{Br_2}$ then two equivalents of $\ce{CH_3CH_2MgBr}$, I can get the corresponding alkane (3,4-dimethylhexane) but I don't see how to do it while preserving the double bond...
... |
Your approach, which uses $\ce{Br2}$ to convert 2-butene into 2,3-dibromobutane and react that with ethylmagnesium bromide $\ce{CH3CH2MgBr}$ has two flaws:
1. This approach removes the alkene and there is no obvious way to get it back (there is away)
2. More seriously, Grignard reagents are pretty terrible for $\... |
Your approach, which uses $\ce{Br2}$ to convert 2-butene into 2,3-dibromobutane and react that with ethylmagnesium bromide $\ce{CH3CH2MgBr}$ has two flaws:
1. This approach removes the alkene and there is no obvious way to get it back (there is a way)
2. More seriously, Grignard reagents are pretty terrible for $... |
It's very difficult to get accurate information concerning the household bleach residues (eg. when washing fabrics). Some sources say it totally "vanished" leaving water + oxygen, some other says it leaves some toxic compounds (such as sodium hydroxide used to slow its decomposition).
If it does leave toxic residue(... |
How can one get 3,4-dimethylhex-3-ene from but-2-ene ?
$\hskip2in$![enter image description here][1]
Using $\ce{Br_2}$ then two equivalents of $\ce{CH_3CH_2MgBr}$, I can get the corresponding alkane (3,4-dimethylhexane) but I don't see how to do it while preserving the double bond...
[1]: https://i.stack.i... |
Can $\ce{Ph-CH2-Ph}$ be also be named as as (phenyl methyl) benzene instead of diphenyl methane?
I came to this thinking that $\ce{CH2-Ph}$ can be considered as side chain at side chain. |
<html>
<head>
<title>Confusion In between Base (not alkali) and C2H5OH</title>
<body>
<font color=red><P>
Since some bases are not alkaline we cant check whether they give OH ions or not<BR>
</font><font color=green>
Ethyl alcohol also has Oh then why it aint a base?
AND I AM A MERE BEGGINER
</Font>
</P>
<... |
Since some bases are not alkaline we can't check whether they give $\ce{-OH}$ ions or not
Ethyl alcohol also has $\ce{-OH}$ then why it aint a base?
|
Since some bases are not alkaline, we can't check whether they give $\ce{-OH}$ ions or not. Ethyl alcohol also has a $\ce{-OH}$ group. Why isn't it a base?
|
How can we balance oxygen or any other diatomic molecule with a fractional coefficient in a reaction? I mean, if we can balance oxygen atoms in an odd number what happens to other oxygen atom, and can this sort of reaction even happen? |
How can we balance one-half of an oxygen molecule, or any other diatomic, in a chemical reaction? |
Since some bases are not alkaline, we can't check whether they give $\ce{OH-}$ ions or not. Ethanol also has a $\ce{-OH}$ group. Why isn't it a base?
|
In a Pourbaix diagram (E-pH diagram) where the regions are given , but the assignment of these to the elements we have is not done yet , how can the oxidation numbers helps me out assigning each element in its appropriate region? |
Consider the following molecule :
![enter image description here][1]
What would it yield by a Lemieux-Johonson oxydation ($\ce{OsO_4,NaIO_4}$) ?
My first guess would have been that $\ce{OsO_4}$ was likely to attack any of the bonds in the cycle (since they are delocalized); but would it stop here, or attack th... |
I have to use dilute salt solutions incredibly frequently, and it takes valuable time to make them from pure reagents every time I need them.
Are concentrated salt solutions fairly stable over time?
Does anyone know of any papers describing their ability to maintain static concentrations for long periods?
|
Are concentrated salt solutions stable over time? |
According to the MSDS for NADPH Tetrasodium Salt, it says to store it in a place away from heat and light. Does this include UV light or just visible light? I was told that a pure NADPH stock solution (with pH 7 phosphate buffer as solvent) could be re-used after absorbing UV light at 340 nm, but based on the MSDS it s... |
Is NADPH sensitive and unstable in UV light? |
I have come across a following line in my textbook- **PI5 does not exist due to steric hindrance**. I searched for the explanation of steric hindrance in wikipedia but couldn't understand it. can anyone explain steric hindrance in simpler language?
Also in wikipedia, it says that "**The existence of PI5 has been cla... |
I have come across a following line in my textbook- **$\ce{PI5}$ does not exist due to steric hindrance**. I searched for the explanation of steric hindrance in wikipedia but couldn't understand it. Can anyone explain steric hindrance in simpler language?
Also in wikipedia, it says that "**The existence of $\ce{PI5}... |
The simplest explanation is that you can not fit five iodine atoms around a phosphorous atom.
Consider the [pentachloride][1] equivalent - this is already quite crowded. Since chlorine atoms have a smaller covalent radius than iodine, you can get five of them around the phosphorous. Of course, all this depends on th... |
I have come across a following line in my textbook- **$\ce{PI5}$ does not exist due to steric hindrance**. I searched for the explanation of steric hindrance in Wikipedia but couldn't understand it. Can anyone explain steric hindrance in simpler language?
Also in Wikipedia, it says that "**The existence of $\ce{PI5}... |
I usually use Gaussian/GaussView and don't have to bother with other programs as I think that GaussView is capable of producing nice orbital/surface pictures like this one of one of uracil's Kohn-Sham-orbitals.![GaussView cube file visualization; uracil LUMO][1]
But when it comes that I have to use other programs th... |
If I have a system in which I introduce $\mathrm{100~e.u.F}$ (energy units) derived from chemical energy (i.e. fuel) and generate thermal energy to heat water what are e.u. absorbed by water? I.e. the efficiency of the transformation?
Basically I would like to know the "average/general" efficiency of energy transfor... |
Consider the following molecule :
![enter image description here][1]
What would it yield by a Lemieux-Johonson oxydation ($\ce{OsO_4,NaIO_4}$) ?
My first guess would have been that $\ce{OsO_4}$ was likely to attack any of the bonds in the cycle (since they are delocalized); but would it stop here, or attack th... |
I have to use dilute salt solutions incredibly frequently, and it takes valuable time to make them from pure reagents every time I need them.
Are concentrated salt solutions fairly stable over time?
Does anyone know of any papers describing their ability to maintain static concentrations for long periods?
Edit:
... |
As a similar idea to the question [A compound that absorbs all visible light][1], I am curious if there is a compound (or compounds) that absorb UV-A radiation (shown below)?
However, preferable the compound would have relatively good transmission in the UV-B and Visible wavelengths.
![enter image description her... |
It seems such a simple formula, that each electron shell can hold in principle two times a square number. I imagine there must be a geometrical reason for this, that's to do with the way electron orbitals "fit" around the nucleus. If this is so, what is it? |
Each electron shell can hold up to 2n² electrons. Is there a geometric reason for this? |
I'm a physicist, so apologies if the answer below is in a foreign language; but this was too interesting of a problem to pass up. I'm going to focus on a particular question: If we have oxygen and nothing else in a box, how strong does the magnetic field need to be to concentrate the gas in a region? The TL;DR is t... |
(Note I've refocused a previous unanswered question into a more general question. You can find the original much more specific question [here][1])
There seems to be two main ways of looking at the enthalpy of substances: molar enthalpy and heat of formation. What are the differences/advantages and disadvantages of eac... |
Molar enthalpy vs Enthalpy of formation? |
Yes, there are many such compounds. "[The evolution of UVA protection][1]" is a nice article detailing the progress on UVA blockers. I'm sure you're aware that sun care is a big business ($8.7 billion USD worldwide in 2013), so there is no shortage of chemists working in the area. In fact, there is enough (medical a... |
I'm wondering if the addition of a base of type $\ce{NR_3}$ (R: alkyl) to a ketone (e.g. 3-Pentanone or 4-Heptanone) results in the cis or trans-enolate.
I didn't find any internet page which studies this question, therefore I'd like to ask here about four cases:
a) $\ce{NMe_3}$ (small)
b) $\ce{NMeEt_2}$ (med... |
The modified Arrhenius equation is used to express the rate constant in a chemical mechanism model I'm working with. The equations is as follows:
$$k_f = A\times T^b\times exp\left(-\frac{E_a}{RT}\right)$$
The paper states that "Units are Moles, cm3, Seconds, K, and Calories/Mole" so what would be the final units of ... |
Units in modified Arrhenius equation? |
Molecular *composition* can be determined in some "primitive" ways ([1][1], [2][2]). What about the molecular structure? Is there a way to know what's bonded to what without spectroscopy etc.?
[1]: http://chemistry.stackexchange.com/questions/771/how-were-elements-and-molecular-formul%C3%A6-determined-in-the-old... |
Can molecular structure be determined without modern characterization methods? |
Molecular *composition* can be determined in some "primitive" ways ([1][1], [2][2]). What about the molecular structure? Is there a way to know what's bonded to what without spectroscopy etc.?
By "modern" I mean any method that emits and detects particles (photons, electrons, etc.).
[1]: http://chemistry.stacke... |
I've been working on Tin electroplating on the side for a while now. I've formulated a mix from my usual electroplating formula template. The mix stubbornly keeps on having the Tin ions to form Tin Hydroxide with water. I've tried adding different organics and complexes in hopes of preventing this. But the Hydroxides k... |
I've been working on Tin electroplating on the side for a while now. I've formulated a mix from my usual electroplating formula template. The mix stubbornly keeps on having the Tin ions form Tin Hydroxide with water. I've tried adding different organics and complexes in hopes of preventing this. But the Hydroxides keep... |
It's very difficult to get accurate information concerning the household bleach residues. Imagine for instance you pour pure or diluted bleach on a fabric or synthetic foam and let it dry without rinsing (as a scientific experimentation). Some sources say: it will totally "vanished" (with air and/or light), leaving wat... |
It's very difficult to get accurate information concerning the household bleach residues. Imagine for instance you pour pure (or diluted) bleach on a fabric or synthetic foam and let it dry without rinsing (as a scientific experimentation). [Some sources][1] say: it will totally "vanished" (with air and/or light), leav... |
It's very difficult to get accurate information concerning the household bleach residues. Imagine for instance you pour pure (or diluted) bleach on a fabric or synthetic foam and let it dry without rinsing (as a scientific experimentation). [Some sources][1] say: it will totally "vanished" (with air and/or light), leav... |
So apparently the Lewis structure of $\ce{SO_2}$ is
![enter image description here][1]
It was my understanding that the central atom is the one that is more electronegative. And an atom is more electronegative the closer it is to Fluorine (top-right). The oxygen is definitely closer to fluorine than sulphur is. T... |
Why is sulphur the central atom in the Lewis structure for SO2? |
It's very difficult to get accurate information concerning the household bleach residues. Imagine for instance you pour pure (or diluted) bleach on a fabric or synthetic foam and let it dry without rinsing (as a scientific experimentation). [Some sources][1] say: it will totally "vanished" (with air and/or light), leav... |
It's very difficult to get accurate information concerning the household bleach residues. Imagine for instance you pour pure (or diluted) bleach on a fabric or synthetic foam and let it dry without rinsing (as a scientific experimentation). [Some sources][1] say: it will totally "vanished" (with air and/or light), leav... |
Does bleach (without rinsing) leave residue(s) and could vinegar or baking soda (or vitamin C) neutralize it? |
> Consider
>
> $$\ce{PCl_3}\\ \ce{CH_2CL_2}\\ \ce{HCN}\\ \ce{SiO_2}$$
>
> Which ones are polar substances?
I appear to be lacking on the concept of "polar substance". I was just studying about Lewis Structures and this question popped in the book, but I'm not quite sure how is this related.
I think that a c... |
How can I tell if a molecule is polar or not? |
The modified Arrhenius equation is used to express the rate constant in a chemical mechanism model I'm working with. The equations is as follows:
$$k_\mathrm{f} = A\times T^b\times\exp\left(-\frac{E_\mathrm{a}}{RT}\right)$$
The paper states that "Units are Moles, cm3, Seconds, K, and Calories/Mole" so what would be t... |
> Consider
>
> $$\ce{PCl3}\\ \ce{CH2Cl2}\\ \ce{HCN}\\ \ce{SiO2}$$
>
> Which ones are polar substances?
I appear to be lacking on the concept of "polar substance". I was just studying about Lewis Structures and this question popped in the book, but I'm not quite sure how is this related.
I think that a chemi... |
It's very difficult to get accurate information concerning the household bleach residues. Imagine for instance you pour pure (or diluted) bleach on a fabric or synthetic foam and let it dry without rinsing (as a scientific experimentation). [Some sources][1] say: it will totally "vanished" (with air and/or light), leav... |
What factors influence the partition factors across a membrane for a chemical species? Wikipedia defines the partition coefficient as:
'In the physical sciences, a partition-coefficient (P) or distribution-coefficient (D) is the ratio of concentrations of a compound in a mixture of two immiscible phases at equilibri... |
What factors influence the partition factors across a membrane for a chemical species? Wikipedia defines the partition coefficient as:
> In the physical sciences, a partition-coefficient (P) or distribution-coefficient (D) is the ratio of concentrations of a compound in a mixture of two immiscible phases at equilibr... |
Is it blueish, perfect white or some other color? I am interested because some celestial bodies are said to be covered with methane ice.
|
What color has the methane ice? |
What color is methane ice? |
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