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Is there a chemical that has the bond structure like below?
(sorry, I found I could not upload the picture. So, I need to describe as below.)
There are 5 atoms linking together.
Two of them have 4 bonds. (They are different atoms.)
Another two of them have 3 bonds. (They can be either same or different atoms.)
T... |
Are there such kinds of chemicals? |
Is 2,3-dimethylprop-1-ene a possible organic structure?
I am not sure how to approach this, what would the correct name of this molecule be? |
Is there a chemical that has the bond structure like below?
![enter image description here][1]
There are 5 atoms linking together.
Two of them have 4 bonds. (They are different atoms.)
Another two of them have 3 bonds. (They can be either same or different atoms.)
The last atom has only 2 bonds.
Are there s... |
I need some help in a electrophilic substitution reaction.
![enter image description here][1]
[1]: https://i.stack.imgur.com/r7SHS.png
What will be the major product formed in this reaction and why? It would be nice if someone can explain me. |
I need some help in a electrophilic substitution reaction.
![enter image description here][1]
What will be the major product formed in this reaction and why? It would be nice if someone can explain me.
[1]: https://i.stack.imgur.com/bfvGQ.png |
I need some help in a electrophilic substitution reaction.
![enter image description here][1]
What will be the major product formed in this reaction and why? It would be nice if someone can explain this to me.
[1]: https://i.stack.imgur.com/bfvGQ.png |
I need some help in a electrophilic substitution reaction.
![enter image description here][1]
What will be the major product formed in this reaction and why? It would be nice if someone can explain this to me.
[1]: https://i.stack.imgur.com/bfvGQ.png
I know that
(1) Activator wins over deactivator.
(... |
What is the best method for predicting the water solubility (and in other solvents) of a compound given its molecular structure?
For instance, I would like to find data about solubility of flavonoids at different pHs. I could not find anything up to now. I would also like to be able to predict complexation constant... |
This is a question that has bothered me for a while. In the past many years, no company has been able to develop a material that can transmit light nearly as well as fiber optic glass, or at least not as cheaply.
After doing a bit of research, I found that although there is fiber optic plastic, the quality is consi... |
What barriers prevent plastic from becoming a fiber optic, data transmission medium? |
This is a question that has bothered me for a while. In the past many years, no company has been able to develop a material that can transmit light nearly as well as fiber optic glass, or at least not as cheaply.
After doing a bit of research, I found that although there is fiber optic plastic, the quality is consi... |
I know sulfuric acid is an important catalyzer and is used in various processes. My question is, how do I recover the remaining sulfuric acid? It will be impure, and I don't know how to do the "standard" process (is there one?) |
I know sulfuric acid is an important catalyzer and is used in various processes. My question is, how do I recover the remaining sulfuric acid? It will be impure, and I don't know how to do the "standard" procedure (is there one?) |
Given some small chemical compounds whose solubility varies with pH, and in the case of compounds that can form complexes, I have seen that the complexation constant varies with pH. I think there might be two main reasons for this; one that chemical structure of the host system is affected by pH (for instance, protonat... |
Given some small chemical compounds whose solubility varies with pH, and in the case of compounds that can form complexes, I have seen that the complexation constant varies with pH. I think there might be two main reasons for this; one that chemical structure of the host system is affected by pH (for instance, protonat... |
My teacher gave us the equations for zero-order, first-order and second-order reactions as follows:
$$ [A]_t = -akt + [A]_0 $$
$$ \ln [A]_t=-akt+\ln [A]_0$$
$$\frac1{[A]_t}=akt+\frac1{[A]_0}$$
Where a is the coefficient of $A$ in the chemical reaction, but everywhere I've seen, the $a$ is not there. I have the... |
A lot of the organometallics are rather... interesting compounds to work with. The most famous (among those who care, anyway) is *tert*-butyllithium or t-BuLi. It is the textbook example of a pyrophoric substance, demonstrated to pretty much every chemistry major as an example of an air-sensitive chemical requiring spe... |
there is a process named solar furnace pyrolysis which is used to reduce the oxides of various elements by concentrating solar energy. oxygen is liberated but still a oxide slag is left.
SiO2 - SiO + 1/2O2 (by pyrolysis)
how can the element can be extracted from the oxide produced?..
i am making a project for na... |
I have recently read many papers where neural networks (NNs) are trained to predict chemical properties (starting from the structure of small chemical compounds) for compounds rather close to the ones with which they were trained. In some cases the predictions are rather good. But I see that apart from the predictive c... |
There is a process named solar furnace pyrolysis which is used to reduce the oxides of various elements by concentrating solar energy. Oxygen is liberated but an oxide slag is left.
$\ce{SiO2 -> SiO + 1/2O2}$ (by pyrolysis)
How can the element can be extracted from the oxide produced?
I am making a project for... |
I've watched over this Khan video titled "Reactions in Equilibrium" and am still confused on the interpretation of equilibrium. [Reactions in Equilirbium][1]
<math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
<msubsup>
<mtext>N</mtext>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
... |
I've watched over this Khan video titled "Reactions in Equilibrium" and am still confused on the interpretation of equilibrium. [Reactions in Equilirbium][1]
<math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
<msubsup>
<mtext>N</mtext>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
... |
I've watched over this Khan video titled "Reactions in Equilibrium" and am still confused on the interpretation of equilibrium. [Reactions in Equilirbium][1]
$\ce{N2(g) + 3H2(g) <=>2NH3(g)}$
Whenever I see an equilibrium like the one above, the amounts of each molecule are only what happens at the start of the re... |
I know that some chemical substances are used as explosives. The most famous maybe are nitroglycerin in [dynamite][1] and cyclonite in [C-4][2]. But which chemical properties (well physical don't play the role, I guess) make one substance to be a good explosive and other even better one? If we know, for example, the fo... |
Which chemical properties make the substance to be explosive? |
I'm going to assume by *'good explosive'* you mean *'high energy to mass ratio'*, which by no means implies anything about whether the explosive is *'good'* in the *'won't suddenly explode when thought about'* sense.
This is not intended to be a full answer as it doesn't touch on the [terrifying explosivity][1] of [... |
This is not the typical chemistry question on this website, but I think it's an important practical question.
When I got a gas string trimmer, the woman who worked at the gardening shop told me that E10 (fuel commonly sold in the USA - 10% Ethanol, 90% gas) left sitting in a gas tank for months would be harmful. So ... |
Is there a point at which Ethanol (E10) fuel becomes harmful to gas tanks or engines if not used? |
Are chiral quasicrystals possible? |
There are, actually, several types of explosives by use: initiating (primary) explosives, secondary explosives and blasting agents.
Initiating explosive must be sensitive to shock/friction, but not too sensitive. The most famous primary explosive is mercury fulminate, but others are known. To act as primary explosiv... |
> However, each reaction at a different temperature has a different equilibrium constant. With that said, the amount of each molecule will change which also changes the concentration so the amount of NH3 would not necessarily be 2.
This is true. I have not watched the video, but if he is suggesting that the stoichio... |
I am looking for some kind of material that can be used to easily latch something to someone's finger. This is for a first year engineering project. The idea is to use this material to latch small motors on someone's fingers in the same way that the motor in [this picture][1] is attached. The person should be able to m... |
I have been looking into certain approximations for band gap energies in quantum dots and have found [this paper](http://chemlabs.nju.edu.cn/literature/materials/GaN/point%20defect/!Band-structure-corrected%20local%20density%20approximation%20study%20of%20semiconductor%20quantum%20dots%20and%20wires.pdf) (Band-structur... |
There is a debate about "how reducing" the atmosphere of the early Earth was, and this question is my attempt to grasp toward an understanding of what that really means.
If anything can be more reducing than something else, it seem like $\ce{CH4}$ gas should be more reducing than $\ce{O2}$, so I'm trying to underst... |
What does it mean for something to be more reducing than something else? |
What happens to the "**[v]olatile molecules** [that] reach the main olfactory epithelium in the nasal cavity" after they bind and the neural stimulus fades?
[CLICK HERE](https://lh3.googleusercontent.com/-mAan9q03Jik/UTLslqb3-5E/AAAAAAAAAOU/uMCzv2DzAS8/s208-c/March22013) |
What happens to the "**[v]olatile molecules** [that] reach the main olfactory epithelium in the nasal cavity" after they bind and the neural stimulus fades? |
1)how does it work? ive read that its about the similarity of the energy levels of 3d and 3p, but shudnt the electron shell 4s be filled before 3d if filled? so what is to do with the 3d???
2)Id also like to know in what cases will atoms of elements expand their valence electrons? like what blocks or groups or perio... |
how do expansion of electron shell works? |
There is a debate about "how reducing" the atmosphere of the early Earth was, and this question is my attempt to grasp toward an understanding of what that that phrase really means. As a bit of context, the [Miller-Urey experiment][1] produces a wide variety of complex organic molecules, but people say it requires a v... |
What does the phrase "reducing atmosphere" mean in quantitative terms? |
We installed an artesian well and we had some surprises.
We asked a few places around and they all told me that we needed 4 different systems to solve our water problem. I am ready to accept this fact but before having our basement transformed to a factory I just wanted to confirm that this is the only solution.
He... |
Do I really need 4 different water treatment systems with this water analysis? |
Do you know any tools that generate electrostatic potential 2d maps of the molecules as an image? |
Tool that generates electrostatic maps of molecules? |
We installed an artesian well and we had some surprises.
We asked a few places around and they all told me that we needed 4 different systems to solve our water problem. I am ready to accept this fact but before having our basement transformed to a factory I just wanted to confirm that this is the only solution.
He... |
What happens to volatile molecules that reach the main olfactory epithelium in the nasal cavity after they bind and the neural stimulus fades?
To what extent do such factors as receptor kinetics and diffusion (or any others) direct where these molecules end up? |
What are the factors controlling the fate of post-adhesed volatile molecules of the olfactory epithelium? |
1. How does it work? I've read that its about the similarity of the energy levels of $3d$ and $3p$, but shouldn't the electron shell $4s$ be filled before $3d$ if filled? So what is done with the $3d$?
2. I'd also like to know in what cases will atoms of elements expand their valence electrons? Which blocks or gro... |
How does expansion of electron shells work? |
I have been looking into certain approximations for band gap energies in quantum dots and have found [this paper](http://chemlabs.nju.edu.cn/literature/materials/GaN/point%20defect/!Band-structure-corrected%20local%20density%20approximation%20study%20of%20semiconductor%20quantum%20dots%20and%20wires.pdf) (Band-structur... |
I'm looking for ways to manipulate molten glass with (e.g. bending a heated glass tube).
[This article][1] mentions that oxides tend to adhere, hence molten glass to heated stainless steel.
What materials could I use to manipulate hot glass? Perhaps I could coat the glass or instrument doing the manipulation wit... |
Could anyone offer a suggestion as to how an economy-minded chemist ought to implement a DIY-ed positive displacement alternative to the following:
 |
If I start with a small amount of a substance, and I dilute that substance with billions of gallons of water, what is the scientific explanation for there being no (actually zero) remaining molecules of that original substance?
This question is related to the practice of homeopathic dilutions. I was reading some art... |
How can a substance be diluted to nothing? |
Does resonance apply to No2+? |
You correctly point out that the number of molecules in a solution is finite and constant, however the volumetric concentration (that is, how many molecules per litre) changes upon dilution. If, for instance, you take one liter of a 1 [mol/L][1] solution of ethanol in water ($\approx{6.02\times{10}^{23}}$ ethanol molec... |
We installed an artesian well and we had some surprises.
We asked a few places around and they all told me that we needed 4 different systems to solve our water problem. I am ready to accept this fact but before having our basement transformed to a factory I just wanted to confirm that this is the only solution.
He... |
So I was wading through several textbooks yesterday reviewing the concepts of buffers. I found them lot more challenging than I used to. One thing in particular disturbed me: The books and internet all said "Yeah, buffers work pretty great in as long as the $\rm pH \approx pK_a\pm 1$." But I am not one to leave these ... |
I have been looking into certain approximations for band gap energies in quantum dots and have found [this paper](http://chemlabs.nju.edu.cn/literature/materials/GaN/point%20defect/!Band-structure-corrected%20local%20density%20approximation%20study%20of%20semiconductor%20quantum%20dots%20and%20wires.pdf) (Band-structur... |
Could anyone identify this for me? It's from a quiz bowl clue that doesn't have the answer with it.
"This linear polyatomic ion containing three atoms of carbon has a negative four charge and is only found bonded with lithium and magnesium."
Thanks! |
>Sesquicarbide
A quick [Google search](https://www.google.com/search?q=li4c3&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a) suggests that $\ce{Li4C3}$ is a real compound, but based on what I saw in the links, it probably is not ionic in the same way that lithium acetylide $\ce{Li2C2}$ is.
... |
I'm trying to get a set of FTIR x/y numerical data points for a couple of elements, namely Silver, Platinum, Palladium, Gold and Sodium. I've looked on line and found images only of the FTIR but I need the numerical x/y data points with the largest wavelength range. I tried NIST but they just show the NMR data. Is ... |
I'm trying to get a set of FTIR or (FTIR like range) x/y numerical data points for a couple of elements, namely Silver, Platinum, Palladium, Gold and Sodium. I've looked on line and found images only of the FTIR but I need the numerical x/y data points with the largest wavelength range. I tried NIST but they just sh... |
I'm trying to get a set of FTIR or (FTIR like range) x/y numerical data points for a couple of elements, namely Silver, Platinum, Palladium, Gold and Sodium. I've looked on line and found images only of the FTIR but I need the numerical x/y data points with the largest wavelength range. I tried NIST but they just sh... |
Not to be confused with [what is the mechanism of acid-catalyzed ring opening of epoxides][1].
>What is the correct order of regioselectivity of acid-catalyzed ring-opening of epoxides: 3<sup>o</sup> > 2<sup>o</sup> > 1<sup>o</sup> or 3<sup>o</sup> > 1<sup>o</sup> > 2<sup>o</sup>? I am getting ready to teach epoxid... |
Extending the pattern of epoxides to bromonium ions and mercurinium ions is hazardous at best. Below the second row (the carbon row) bond lengths get much longer, and acid strengths are much lower than compared to sulphuric acid in methanol.
In general acid-catalyzed reactions involving epoxides where selectivity ... |
My textbook said $\ce{NO2+}$ and $\ce{NO2-}$ both have resonance structures, now I am a little bit confused since I cannot figure out the resonance structure for $\ce{NO2+}$.
What is it? |
Does resonance apply to NO2+? |
I've already searched online some information about this equation, but everywhere I read, there's also Sulphuric Acid, which in the laboratory, we did not use. We only used Potassium Permanganate and Oxalic acid and water, there was no sulphuric acid. The purpose of the laboratory was to calculate experimentally the r... |
What is the reaction between Oxalic Acid and Potassium Permanganate? |
Why is NaCl more soluble in water than NaOH? Well, this is a question from Chemical Equilibrium and the question hints for explanation in terms of Le Chatelier's principle. Plz help! |
Not to be confused with [what is the mechanism of acid-catalyzed ring opening of epoxides][1].
>What is the correct order of regioselectivity of acid-catalyzed ring-opening of epoxides: 3<sup>o</sup> > 2<sup>o</sup> > 1<sup>o</sup> or 3<sup>o</sup> > 1<sup>o</sup> > 2<sup>o</sup>? I am getting ready to teach epoxid... |
A very simple test for the presence of alcohols in the lab involves adding Ceric(IV) Ammonium Nitrate solution which gives a pinkish red colour in the presence of alcohol.
When I looked up the structure of [this compound] it turns out to be quite interesting. So a couple of questions about lanthanides came up in my... |
A very simple test for the presence of alcohols in the lab involves adding Ceric(IV) Ammonium Nitrate solution which gives a pinkish red colour in the presence of alcohol.
When I looked up the structure of [this compound] it turns out to be quite interesting. So a couple of questions about lanthanides came up in my... |
I've already searched online some information about this equation, but everywhere I read, there's also Sulphuric Acid, which in the laboratory, we did not use. We only used Potassium Permanganate and Oxalic acid and water, there was no sulphuric acid. The purpose of the laboratory was to calculate experimentally the r... |
A very simple test for the presence of alcohols in the lab involves adding Ceric(IV) Ammonium Nitrate solution which gives a pinkish red colour in the presence of alcohol.
When I looked up the structure of [this compound] it turns out to be quite interesting. So a couple of questions about lanthanides came up in my... |
During the formation of a molecule of water (H2O), what kind of bond occurs between the elements? I'm studying this subject on my own and from some sources I saw that there is a covalent bond and others showed an hydrogen bond, responsable for the non-evaporation of water at -90^oC. Can you guys explain to me exactly h... |
I'm looking for the dipole transition matrix elements for electronic transitions between the ground and excited states of the carbon dioxide cation, $\text{CO}_2^+$, that is, objects like
$$\langle\text{CO}_2^+ \,\tilde{\text{A}}\,\Pi_\text{u}|\mathbf{r}|\text{CO}_2^+ \,\tilde{\text{X}}\,\Pi_\text{g}\rangle.$$
I feel... |
Database for molecular dipole transition moments? |
As a surprise gift to a friend I would like to discover a new theoretical mineral and have it named after them. I have some understanding that not all minerals have been discovered, and some minerals exist in theory but have not been found on earth.
Is there a computer search that looks for new minerals? Would it be... |
Are there computer searches for new theoretical minerals in a similar vein to Folding@Home or SETI@Home? |
A lot of the organometallics are rather... interesting compounds to work with. The most famous (among those who care, anyway) is *tert*-butyllithium or t-BuLi. It is the textbook example of a pyrophoric substance, demonstrated to pretty much every chemistry major as an example of an air-sensitive chemical requiring spe... |
During the formation of a molecule of water ($\ce{H2O}$), what kind of bond occurs between the elements? I'm studying this subject on my own and from some sources I saw that there is a covalent bond and others showed an hydrogen bond, responsible for the non-evaporation of water at $-90\ ^{\circ} \rm{C}$. Can you guys ... |
A very [simple test] for the presence of alcohols in the lab involves adding Ceric(IV) Ammonium Nitrate solution which gives a pinkish red colour in the presence of alcohol.
When I looked up the structure of [this compound] it turns out to be quite interesting. So a couple of questions about lanthanides came up in ... |
<p>
Chemistry - Stack Exchange is for <span class="revision-comment">scientists, academics, teachers and students of <b>chemistry</b></span>.
</p>
<p>Questions may be of any level, but should be of the following types:</p>
- Questions asking for explanation of a chemistry concept
- Questions relating to obser... |
I'm writing a script and would like to use a "Gödel numbering" to search for specific reactions.
Is there any used procedure to assign an symbol (integer, possibly) to a chemical reaction? E.g.
$$CH_4+4O_2=CO_2+2H_2O\ \ \ \Longrightarrow \ \ \ 121231412$$ |
Is there any kind of program that is able to calculate the end result of a specific chemical reaction? Say I wanted to know what happens when you mix HClO + NaOH, is there anything that could give me the answer to any question like this? |
Is there any kind of program that is able to calculate the end result of a specific chemical reaction? Say I wanted to know what happens when you mix HClO + NaOH, is there anything that could give me the answer to any question like this? Wolfram alpha works pretty good, but it doesn't give me an answer if it isn't a ba... |
I have two identical graphite strips of dimensions 3.5cm by 1cm. Both are 3/4 submerged in aqueous NaCl solution (0.34mol/dm3, 2%wt) with a distance of 7cm apart. I attached crocodile clips to each strip and a voltmeter is used to records the potential difference between the two.
I have found that:
A. There is a ... |
Cu has an anomalous electron configuration. Cu = $1s^22s^22p^63s^23p^64s^13d^{10}$, it does not follow the usual pattern. In this case, the 3d subshell is filled before the 4s, which usually happens in the reverse order ($1s^22s^22p^63s^23p^64s^23d^{9})$.
My question is, can you tell by an element's position on the ... |
The Electron Affinity of a neutral Oxygen atom is -142 KJ (it releases this energy). The Electron Affinity for the now anionized Oxygen is 710 KJ (Work must be done on the atom).
My question is, why the large jump in Electron affinity? We are taught that the electrons do not interact much with each other in the way... |
Why does Oxygen not like to be doubly Anionized? |
The Electron Affinity of a neutral Oxygen atom is -142 KJ (it releases this energy). The Electron Affinity for the now anionized Oxygen is 710 KJ (Work must be done on the atom).
My question is, why the large jump in Electron affinity? We are taught that the electrons do not interact much with each other in the way... |
CaF2 is Insoluble in water , but CaCl2 , CaBr2 , CaI2 are soluable ? would anyone please explain why CaF2 is insoluble in water , but CaCl2 , CaBr2 , CaI2 are soluable ? |
Question: Suggest an explanation for the coordination number in the CsCl lattice being different from those in NaCl.
Standard answer: Caesium ion is larger than sodium ion, hence it can be surrounded by greater number of chloride ions.
My question:
1. Question didn’t specify whether it is asking for the coord... |
A couple months ago, one of my room mates accidentally used a cup of salt to make [apple crumble](http://allrecipes.com.au/recipe/9877/the-perfect-apple-crumble.aspx). She asked if there was any way to separate it, probably because I had recently reduced the acidity of a tomato sauce by adding baking soda. I said "prob... |
Is it possible to separate salt from food, or at least convert it into something that doesn't taste salty? |
After a lot of digging around, I finally found some of the answers in J.D. Lee's Concise Inorganic Chemistry. I thought I'd post whatever I found over here anyway since it's very interesting:
Answer to question 2
Complex formation by Lanthanides is different from that of Actinides. In Lanthanides, the $4f$ orbita... |
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