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Uranyl formate has a structure something like:
$\ce{UO2-(OCHO)2}$
So the structural formulae I've seen have two double-bonded oxygens directly attached to the U and each formate group is attached by single bonds to the oxygens. Like <a href="http://images.chemnet.com/suppliers/chembase/cas3/cas16984-59-1.gif">thi... |
Was there any logic or thinking behind the experiments performed by Cannizzaro, Beckmann, Gattermann, Koch etc.?
Did they thoughtfully perform experiments or just add any two reactants and luckily discovered the reactions which are known by their name today?
I meant to ask that in Physics all problems are treat... |
When I have a Gadolinium ion (3+ $\ce{\Longrightarrow Gd^3+}$), how can I calculate its electron configuration?
electron configuration of $\ce{(Gd)} = \ce{[Xe]}4f~^7 5d^1 6s^2$
Do I need to first subtract the 2 electrons in the s-orbital and then the (d/f)orbital? |
Is there a kind of table about configurations similar to the example I gave below? |
Wiki says:
> [Oxidation state] is defined as the charge an atom might be imagined to have when electrons are counted according to an agreed-upon set of rules:
> The oxidation state of a free element (uncombined element) is zero
for a simple (monoatomic) ion, the oxidation state is equal to the net charge on th... |
I was wondering if anyone had any insight as to why the reaction of chlorosulfonic acid (colorless) and 1-dodecanol (colorless) produces a deep dark-red-colored solution? The reaction should give hydrogen lauryl sulfate, which according to [this website](http://www.guidechem.com/dictionary/151-41-7.html), is a white so... |
Why does the reaction of chlorosulfonic acid (colorless) and 1-dodecanol (colorless) produces a deep dark-red-colored solution? |
How to know if the following chemical structure of morphine is an R or S? What I basically need to know is: which chirality center do we use to make the decision?
$\hskip2in$![enter image description here][1]
[1]: https://i.stack.imgur.com/7dWojt.png |
Can anyone tell me what the difference between catenation and allotropy is? I would like the basic explanation. |
Common saying. <br>**Ultra hardness,** (*10 on Moh's scale; 10000 HV on Vicker's Hard Test (iron merely 30-80))*<br> **hyper thermal conductivity,** (*2320 W*$m^{-1}$*$K^{-1}$, or over ten times better than the heatsink <br>in your computer!*) <br>**extreme pressure resistance,** *(withstands a crushing 600 gigapascals... |
[According to Wikipedia,][1] a **vacuum airship** is a hypothetical airship that is evacuated instead of using a lighter gas. Really, once I first saw this, I thought, "Why did I never think about this before?!" Indeed, whenever I pictured an evacuated container, I thought it would just sit there. <br> But *no*. Instea... |
Could a vacuum airship be possible? |
I add an other answer : it depends what kind of people you are, if you are as crazy as them, of course not !
[2012 Christmas Lectures - Burning a Diamond][1]
But [ron][2]'s answer is better sure ! ;)
[1]: https://www.youtube.com/watch?v=1QbHRLpYc-0
[2]: http://chemistry.stackexchange.com/users/4231/ron |
Common saying.
- **Ultra hardness,** (*10 on Moh's scale; 10000 HV on Vicker's Hard Test (iron merely 30-80))*
- **hyper thermal conductivity,** (*$2320~\mathrm{W\, m^{-1}\, K^{-1}}$, or over ten times better than the heatsink in your computer!*)
- **extreme pressure resistance,** *(withstands a crushing 600 gig... |
> how long would it take for this super-material to convert to the stuff
> I scribble with?
No, despite the fact that James Bond said "[Diamonds are Forever][1]", that is not exactly the case. Although Bond's statement is a fair approximation of reality it is not a scientifically accurate description of reality.
... |
In a book it is stated that one reason for the failure of Bhor's theory was the fact that it violate uncertainty principle. Is the fact true? if so explain me how it violates uncertainty principle. |
In a book, it is stated that one reason for the failure of Bohr's theory was the fact that it violates the Uncertainty Principle. Is this fact true? if so, explain to me how it violates the Uncertainty Principle. |
Does Bohr's theory violate the Uncertainty Principle? |
Zinc sulphide is used in road signs because when light from cars hit the road signs, it glows. What actually is the reason for the glowing of road signs (actually glowing of ZnS) ? |
Why does Zinc sulphide glow? |
I line dry my cloths and every now, they become rough after drying. This mostly happens with socks. They are regular cotton socks and once I start to wear them they become soft again. Any idea why this is happening? |
Why some cloths become rough after drying? |
Zinc sulphide is used in road signs because when light from cars hit the road signs, it glows. What actually is the reason for the glowing of road signs (actually glowing of $\ce{ZnS}$) ? |
Concrete and sand are highly unreactive to most of the chemical attacks. But chlorine triflouride is so dangerous that it will ignite concrete, sand and other fire retarding substances. Which property does ClF3 possess to cause this ignition and why? |
Lets pretend that on other universe we have an element with atomic number 6, like our carbon, but in this other universe even with the same atomic number it is completely different from our carbon, like a new element with other properties.
Is that a possible scenario? |
Can our chemical elements be differents on other universes? |
Let's pretend that in other universe we have an element with atomic number 6, like our carbon, but in this other universe the element is completely different from our carbon, like a new element with other properties.
Is this a possible scenario? |
Here, I am referring Valence Bond Theory by VBT and Molecular Orbital Theory by MOT.
1.In VBT, atomic orbitals of the combining atoms retain a large amount of their individual character. (For example, see [Orbital Hybridization](https://en.wikipedia.org/wiki/Orbital_hybridisation)).
Whereas, in MOT atomic orbital... |
![enter image description here][1]
The question was to rationalize it the ring cleavage happens concerted or non-concerted.
The papers *"The Mechanism of the Thermal Decomposition of
1-Pyrazolines and Its Relationship to
Cyclopropane Isomerizations"* (Crawford 1965/1966; Original papers: [here][2] and [here... |
I was doing some IR calculations on different 3d transition metal carbonyl complexes during some practical courses where we were introduced to effective core potentials. While doing this we found that MP2 has some problem with the calculation of at least the asymmetrical $\nu_\text{CO}$ band (that was the only one we w... |
Why is MP2 failing to calculate proper IR frequencies for [Co(CO)4]^- and [Fe(CO)4]^{2-}? |
I have a gas (CO2 for example) and I want to infuse it into a liquid (H20 for example). I need a higher pressure of CO2 to do this. So I push in water into a sealed container at 7psi as well as CO2, but at 14psi instead.
Is this possible? Will it back up? What if I use a check valve? Can I use a non-electrical actua... |
Can you push a liquid and a gas into a container at different pressures? |
I have a gas ($\ce{CO2}$ for example) and I want to infuse it into a liquid ($\ce{H2O}$ for example). I need a higher pressure of $\ce{CO2}$ to do this. So I push in water into a sealed container (at 7 psi) and add $\ce{CO2}$ (at 14 psi).
Is this possible? Will it back up? What if I use a check valve? Can I use a no... |
I was doing some IR calculations on different 3d transition metal carbonyl complexes during some practical courses where we were introduced to effective core potentials. While doing this we found that MP2 has some problem with the calculation of at least the asymmetrical $\nu_\text{CO}$ band (that was the only one we w... |
Recently I have read about both of the concepts in my book (Physical Chemistry by Atkins, Paula). It was literally a reading; though I could understand the language and superposition of orbitals, inversion symmetry, and so on, I never could really comprehend how these two theories differ (or agree) with each other. I h... |
I'm a bit new in chemistry, so I need help with a couple of things. Although I don't mind complicated answers, please try to keep it around high school level, and not rocket science. Thanks!
1. Can someone describe exactly what makes a compound a compound? Is it just the simple definition of "multiple elements combi... |
How can I improve this experiment? |
Does flipping a reaction change the sign of the value of E or is it a completely different value?
For example if I have the value for the half reaction Cl2 + 2e- --> 2Cl- but need the value for the opposite reaction (2Cl -> Cl2 + 2e-), do I just put a negative sign and treat it like delta H values? |
Does flipping a reaction change the sign of the value of E or is it a completely different value?
For example if I have the value for the half reaction $\ce{Cl2 + 2e- -> 2Cl-}$ but need the value for the opposite reaction ($\ce{2Cl -> Cl2 + 2e-}$), do I just put a negative sign and treat it like $\Delta H$ values? |
I have **15 liters of aqueous solution** inside an aluminum stock pot which rests upon a hot plate. I want to **reduce the boiling point from 150°C to 100°C using reduced pressure**.
What is the **most economical way efficiently to dry the solute**? Economical means does not require specialty equipment (i.e., labora... |
I have **15 liters of aqueous solution** inside an aluminum stock pot which rests upon a hot plate. I want to **reduce the boiling point from 150°C to 100°C using reduced pressure**.
What is the **most economical way efficiently to dry the solute**? Economical means does not require specialty equipment (i.e., labora... |
Does flipping a reaction as written change the sign of the value of E or is it a completely different value?
For example if I have the value for the half reaction $\ce{Cl2 + 2e- -> 2Cl-}$ but need the value for the opposite reaction ($\ce{2Cl- -> Cl2 + 2e-}$), do I just put a negative sign and treat it like $\Delta... |
Question says it all. I am just curious if a reverse osmosis system can clean water from radioactive element like cesium-134 and cesium-137. If it can, how efficient can it be?
|
I don't know about cesium in particular, but according to the EPA's [web site](http://water.epa.gov/drink/contaminants/basicinformation/radionuclides.cfm) (see the section called "How will radionuclides be removed from my drinking water?"), both isotopes should be covered under the beta particle section.
I cannot q... |
Recently I have read about both of the concepts in my book (Physical Chemistry by Atkins, Paula). It was literally a reading; though I could understand the language and superposition of orbitals, inversion symmetry, and so on, I never could really comprehend how these two theories differ (or agree) with each other. I h... |
I’m needing a method to turn cotton into a fine powder for use as a source of cellulose. What suggestions would you give to accomplish this with materials/tools that could be obtained at local stores? |
What Methods Would I Use To Powder Cotton? |
The content of cellulose in paper is not as high as that of cotton, however, it may be easier to use as a source if you do require a fine powder. Why do you require cellulose? |
I am curious to know if a reverse osmosis system can clean water from radioactive elements like cesium-134 and cesium-137. If it can, how efficient can it be?
|
Can a reverse osmosis system remove radioactive elements in contaminated water? |
Beryllium carbonate is reported to be unstable under normal conditions and only be kept in a atmosphere of CO2. Why and how this stability is maintained? Why this compound decomposes when kept in atmosphere of oxygen? |
>Why and how is this stability maintained?
Beryllium carbonate decomposes into Beryllium oxide and Carbon dioxide.
$$\ce{BeCO3 <=> BeO + CO2}$$
According to [Le Chatelier's principle][1] one simply has to store it under a $\ce{CO2}$ atmosphere to push the equilibrium to the left.
$$\ce{BeCO3 <<=> BeO + CO2}~\te... |
In the reaction of $\ce{LiAlH4}$ with carboxylic acids, deprotonation is followed by a step in which $\ce{O-AlH2-}$ acts as a leaving group. The mechanism is given [here](http://chemistry.stackexchange.com/questions/4940/lialh%E2%82%84-with-carboxylic-acid) in this answer.
$\ce{LiAlH4}$ does not, however, reduce alco... |
Why can't LiAlH4 react with alcohols? |
Beryllium carbonate is reported to be unstable under normal conditions and should only be kept in a atmosphere of $\ce{CO2}$. Why and how this stability is maintained? Why does this compound decompose when kept in an atmosphere of oxygen? |
I've always known $\ce{BH3}$ as a reagent for alkene hydroboration. Recently in class we talked about its use as a reducing agent for carboxylic acids too (it reduces them to alcohols). Now obviously $\ce{BH3}$ is an electrophile and I don't think it reacts by donating hydrides like $\ce{NaBH4}$ does - in any case it's... |
What is the rule for the punctuation marks within the bracketed figures for a bicyclo conpund ? Is it a 'dot' or 'comma'. In some books there are commas whereas dots in some others. |
What is the rule for the punctuation marks within the bracketed figures for a bicyclo compound? Is it a 'dot' or 'comma'? In some books there are commas whereas dots in some others. |
What is the rule for the punctuation marks for a bicyclo compound? |
What is the rule for the punctuation marks within the bracketed figures for a bicyclo conpund ? Is it a 'dot' or 'comma'. In some books there are commas whereas dots in some others. |
What is the rule for the punctuation marks within the bracketed figures for a bicyclo compound? Is it a 'dot' or 'comma'? In some books there are commas whereas dots in some others. |
What is the rule for the punctuation marks for a bicyclo compound? |
Non of the standard undergraduate textbooks in analytical chemistry (such as Skoog, Harris) discusses conductometry as an analytical technique. I wonder whether this technique is obsolete. Or is it taught under some other area such as physical chemistry ?
Can someone please point me to some good references on this ... |
What are some good references on conductometry as an analytical technique? |
I know that Quantum Dots have high quantum yield and ranges from 2nm-10nm, and Nanoclusters have high fluorescence and ranges from 1nm-10nm. But the difference between them is that Quantum Dots exhibits red shift as the size gets larger while vice versa for Nanoclusters. My guess is Quantum Clusters is the combination ... |
What is the main difference between Quantum Clusters and Nanoclusters? |
I am certainly no expert in the field (in fact, I know nothing about it) but I imagine this 225+ page text will prove to be useful for you:
[Oscillometry and Conductometry: International Series of Monographs in Analytical Chemistry, Volume 21](https://books.google.com/books?id=o8X9BAAAQBAJ&pg=PR13&dq=conductometry&hl=... |
>If I choose GIAO HF/STO-3G, is the default solvent $\ce{CD3Cl}$?
No, the default is gas phase as usual. But you can choose whatever solvent is programmed through the scrf=(solvent=...) command. The available solvents are listed at the bottom of the [related Gaussian keyword site][1].
>Is the default frequency fo... |
Noble metals are close to filling both $s$ and $d$ subshells, so there is a certain stability in gaining electrons. Gold atoms in complexes form bonds with each other similar in strength to hydrogen bonds and can form stable $\ce{Au^-}$ salts with cations like $\ce{Cs^+}$. Platinum similarly forms $\ce{Pt^{2-}}$. There... |
>If I choose GIAO HF/STO-3G, is the default solvent $\ce{CD3Cl}$?
No, the default is gas phase as usual. But you can choose whatever solvent is programmed through the scrf=(solvent=...) command. The available solvents are listed at the bottom of the [related Gaussian keyword site][1].
>Is the default frequency fo... |
I just did a lab that involved heating KClO<sub>3</sub> (with MnO<sub>2</sub> as a catalyst) to decompose it into KCl and oxygen gas. That part is easy. What's throwing me is the % yield calculations.
The theoretical yield of O should just be the mass percentage of O in KClO<sub>3</sub> (48.00/122.55 = KClO<sub>3</s... |
Why are the mass ratios of O to KClO3 and O2 to KClO3 the same? |
I just did a lab that involved heating KClO<sub>3</sub> (with MnO<sub>2</sub> as a catalyst) to decompose it into KCl and oxygen gas. That part is easy. What's throwing me is the % yield calculations.
The theoretical yield of O should just be the mass percentage of O in KClO<sub>3</sub> (48.00/122.55 = KClO<sub>3</s... |
I'm confused about sp2 hybridization in the formation of NO3- ion. Valence electrons of N are 2s2 and 2p3. Is one of s2 electrons kicked up to one of the 2p orbitals, and then the remaining s electron is hybridized with the two remaining p orbitals which have unpaired electrons? If so, that gives sp2 orbitals to bon... |
I recently purchased some 55 gallon blue barrels for rainwater harvesting. Upon closer inspection of the barrels, I noticed they previously housed food grade sodium hypochlorite which was used to wash produce. I was searching for food grade barrels but wasn't expecting bleach. Because I will be watering plants and f... |
I recently purchased some 55 gallon blue barrels for rainwater harvesting. Upon closer inspection of the barrels, I noticed they previously housed food grade sodium hypochlorite which was used to wash produce. I was searching for food grade barrels but wasn't expecting bleach. Because I will be watering plants and f... |
I recently purchased some 55 gallon blue barrels for rainwater harvesting. Upon closer inspection of the barrels, I noticed they previously housed food grade sodium hypochlorite which was used to wash produce. I was searching for food grade barrels but wasn't expecting bleach. Because I will be watering plants and f... |
I am trying to calculate PES for Molecular Oxygen and Atomic Nitrogen Exchange reaction. This is also known as Zeldowich reaction. I found that for asingle reactions, there are many PES's which I believe are for different electronic configurations of the NO2 PES. I found that the multiplicity can be 2 or 4. Also I fin... |
Why is distance weighted interpolation done in the predictor steps, instead of doing it in the correcter steps? I got stuck while reviewing the journal "Accurate reaction paths using a Hessian based predictor–corrector integrator".
The link is http://scitation.aip.org/docserver/fulltext/aip/journal/jcp/120/21/1.172482... |
Selenium is a good conductor of electricity in presence of light. This phenomenon is called photoconductivity. How does this phenomenon occur? Does there exist any other element or compound in which this phenomenon is noted? |
Why do transition metals tend to form positive ions instead of negative ions? |
I got stuck while reviewing the journal article "Accurate reaction paths using a Hessian based predictor–corrector integrator".
Why is the distance weighted interpolation done in the predictor steps, instead of doing it in the correcter steps?
Source: [H. P. Hratchian and H. B. Schlegel, *J. Chem. Phys.* **2004*... |
Selenium is a good conductor of electricity in presence of light. This phenomenon is called photoconductivity. How does this phenomenon occur? Are there any other elements or compounds in which this phenomenon is noted? |
Does there exist any data repository of chemical compound that gives the structure of the compounds with the help of coordinate geometry. It would be like each atom has a coordinate and the list of bonds it has with other atoms so that the 3D structure of the compound can be created from this very theoretical descripti... |
What are you afraid of exactly? The quantity of bleach remaining after the rinse is certainly miniscule, and it will exponentially drop each time you refill the barrels with rain water.
If you're really concerned (which IMO you shouldn't be), you can refrain from using the water you collect the first time. Also, the... |
I just recalled, and still see that almost every organic chemistry book starts with bonds, empahsizing hybridization. One thing is straight forward but the rest doesn't seem to connect well.
The thing that's clear is, energy level wise sp < sp<sup>2</sup> < sp<sup>3</sup>. When `p` character is higher, the energy is... |
Why does hybridization significantly matter for organic chemistry? |
Orbital hybridization is mostly useful in the explanation of *molecular geometry*. In fact it was invented by Linus Pauling for this purpose: to explain the structure of organic molecules using the language of atomic orbitals. Yes, hybridization is also used to explain bonding properties, as well as acidity or basicity... |
I just recalled, and still see that almost every organic chemistry book starts with bonds, empahsizing hybridization. One thing is straight forward but the rest doesn't seem to connect well.
The thing that's clear is, energy level wise $\mathrm{sp < sp^2 < sp^3}$. When $\mathrm{p}$ character is higher, the energy is... |
In the above mentinoned species Cu2+ ion is has 9 electrons in *3d* orbital with only ome unpaired electron. Then how is it becoming a square planar species ? Where is that unpaired electron going then ? |
Why [Cu(NH3)4]^2+ is a square planar species and not a tetrahedral species? |
Suppose $Na^+$ and $Cl^{-}$ make ionic bond. In doing so they will come closer by attraction. Now as they come closer their speed will increase and hence the kinetic energy. So basically the electrostatic potential energy will be controverted into kinetic energy.
>- My question is why do these processes that involve... |
Why does attraction always cause release of energy? |
I'm confused about $\mathrm{sp^2}$ hybridization in the formation of $\ce{NO3-}$ ion. Valence electrons of N are $\mathrm{(2s)^2}$ and $\mathrm{(2p)^3}$.
Is one of $\mathrm{2s}$ electrons kicked up to one of the $\mathrm{2p}$ orbitals, and then the remaining $\mathrm{2s}$ electron hybridized with the two remaining $... |
Suppose $\ce{Na^+}$ and $\ce{Cl^-}$ form an ionic bond. In doing so they will come closer by attraction. Now as they come closer their speed will increase and hence the kinetic energy increases. So basically the electrostatic potential energy will be controverted into kinetic energy.
>- My question is why do these p... |
Suppose $\ce{Na^+}$ and $\ce{Cl^-}$ form an ionic bond. In doing so they will come closer by attraction. Now as they come closer their speed will increase and hence the kinetic energy increases. So basically the electrostatic potential energy will be controverted into kinetic energy.
>- My question is why do these p... |
I have this question for a long time that in LASER when we do the pumping by heating how does molecular collision causes the atoms(molecules) to reach in excited state. E.g. in $\ce{He-Ne}$ laser when the excited $\ce{He}$ atom collides with the Ne atom the $\ce{Ne}$ atom gets excited and $\ce{He}$ atom reaches its gro... |
How does molecular collision excites the electron? |
The answer has to do with [pi-backbonding][1].
In essence, the CO molecule has a negative formal charge on the carbon (it's neutral because of the oxygen having a positive formal charge). However, C is quite electropositive, and would like to relieve the stress caused by the negative formal charge. To relieve the s... |
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