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While revisiting some of my old notes about the Miller-Urey experiment, I stumbled across the "equation"...
> Electricity + CH4/NH3/H2O/CO = Amino Acids
This got me thinking.
**Conventionally, why are molecules like CH4 and NH3's molecular formula written differently (in H placement) than others like H20 and H... |
While revisiting some of my old notes about the Miller-Urey experiment, I stumbled across the "equation"...
> Electricity + $\ce{CH4~/~ NH3~/~H2O~/~CO}$ = Amino Acids
This got me thinking.
Conventionally, why are molecules like $\ce{CH4}$ and $\ce{NH3}$'s molecular formula written differently (in H placement) ... |
> **Possible Duplicate:**
> [Why is arsenous acid denoted $\ce{H3AsO3}$?](http://chemistry.stackexchange.com/questions/537/why-is-arsenous-acid-denoted-ceh3aso3)
<!-- End of automatically inserted text -->
While revisiting some of my old notes about the Miller-Urey experiment, I stumbled across the "equation"...
... |
Can I pipette concentrated sulfuric acid using a plastic pipette tip? Will either the plastic or the acid be affected? |
While revisiting some of my old notes about the Miller-Urey experiment, I stumbled across the "equation"...
> Electricity + $\ce{CH4~/~ NH3~/~H2O~/~CO}$ = Amino Acids
This got me thinking.
Conventionally, why are molecules like $\ce{CH4}$ and $\ce{NH3}$'s molecular formula written differently (in H placement) ... |
crystal of a newly developed explosive called hexamethylene, "Hex" for short. Hex is 80 times more powerful than C4.
i want to know what is the last terms of this interaction:
$$C_6H_{12}N_2O_6 \to ?+E$$ |
[Hexamethylene triperoxide diamine](http://en.wikipedia.org/wiki/Hexamethylene_triperoxide_diamine), "Hex" for short, is an explosive.
I want to know the products of this reaction:
$$C_6H_{12}N_2O_6 \to ?+E$$ |
I'm a non-chemist attempting to put together a chemistry paper. Up to now I've got my thermodynamic data from various random pdf files found on the web, together with Wikipedia. Now that the paper is nearly finished I need to replace these with values from a single, respectable source. But I've realised I don't know ho... |
standard reference for thermodynamic properties? |
Is there a way to make a liquid, such as a liquid crystal material, transition from cloudy or clear and vice-versa using only electric current?
By cloudy, I mean, similar to the effect that cholesterol or [5CB][1] exhibits, thermally.
If so, where could this be obtained, and how quickly does it switch between sta... |
Is there a liquid crystal or similar material that gets cloudy when an electric field is applied, but is otherwise clear? |
Battery leaks was an issue in the 80s and 90s, and since quality and innovation is constantly improving, I thought battery leak might be slowly going away. But I found that even nowadays, name brand alkaline batteries still leak after a while, even if originally concealed in a tight package of the metal shell. Is it ... |
Does the chemical in an alkaline battery make battery leaks unavoidable? |
I think the [CRC Handbook of Chemistry and Physics][1] is a very good source to look for all sorts of physical or chemical data and it can be considered as a kind of standard reference. You can also find an Internet version of the book which would be a bit more "lightweight" than the printed book with its more than 260... |
I am currently reading [this German paper][1] on the dissolution of phosphates by acids and chelants.
The authors do a "fast-test" of the dissolving power of different acids which goes as follows:
> For each test, increasing quantities (10-50ml) of 0.1 n acids are
> added to 100 mg of tricalcium phosphate and ag... |
I have a few cases of brand-new, nitrile gloves of a type and vendor that *used* to be good. But apparently, the vendor has moved manufacturing to a different country and outsourced customer service to Hell. I can't return the gloves.
The gloves all have a chemical smell, resembling a burnt transistor with a hint o... |
How can I identify and neutralize the chemical leaching out of new nitrile gloves? |
Many of us have experienced the failure of nitrile gloves when exposed to chloroform. What's going on at a mechanistic level when this occurs?
I would guess that the chloroform dissolves some of the polymer into its constituent monomers, but I've never heard anything more definite than that. Is it a similar mechani... |
How does chloroform degrade nitrile gloves? |
I have a few cases of brand-new, nitrile gloves of a type and vendor that *used* to be good. But apparently, the vendor has moved manufacturing to a different country and outsourced customer service to Hell. I can't return the gloves.
The gloves all have a chemical smell, resembling a burnt transistor with a hint o... |
I know almost nothing beyond 10th grade chemistry. I'm trying to name a web application, and was wondering what the products are of a reaction between the element Chromium and the gas Ozone (ozonolysis of chromium?).
Thanks,
(I'm not sure I tagged this correctly either. I'm sure this isn't organic so...) |
Chromium + Ozone Reaction Products? |
I too usually refer to the [CRC Handbook][1]. Both of my copies (86th ed, 2005-06 and 46th ed, 1965-66) have a section on thermodynamic properties of materials. The CRC Handbook works for the most of the general data I need to look up. There is some field-specific data I need that isn't in the CRC Handbook; I use the [... |
Sorry for the super simple question... Which of the following possesses the highest energy electron?
A) Br-
B) Ca++
C) Cr+
D) As
Don't Bromine and Arsenic have equally high energy electrons (i.e. in the 4p orbital)??? My book says that Arsenic is the correct answer (D). But I don't see why Br- is wrong. |
Highest Energy Electron - possible typo in my book? |
While performing an inventory of my school's chemical storage closet today, my fellow teacher and I found some sodium tucked away in the back corner of our flammables cabinet. One container appears to have leaked the oil the sodium was being stored in, and we aren't sure about the second container. We don't know how ... |
I'm working through *Chemistry - Principles and Practice, 3rd Edition* and I have few complaints so I don't think it's the text. At one point, I was asked to draw the Lewis structure, with formal charge, of SO<sub>3</sub>. The central sulfur atom has six covalent bonds with the surrounding oxygen atoms. Based on the ca... |
Why don't atoms with expanded valence shells have a formal charge? |
(I will update my answer with some structures later)
Formal charge is the difference between the number of valence electrons that a neutral unbonded atom has and the number of valence electrons assigned to that atom when after it forms bonds in a molecule. It looks like you are making your mistake in assigning the p... |
Formal charge is the difference between the number of valence electrons that a neutral unbonded atom has and the number of valence electrons assigned to that atom when after it forms bonds in a molecule. It looks like you are making your mistake in assigning the proper number of electrons to the sulfur atom.
The ele... |
I know that the answer to this question will vary by country, but some aspects must be similar amongst those countries that have authorities overseeing chemical and industrial hygiene. The [Wikipedia article](http://en.wikipedia.org/wiki/Msds#National_and_international_requirements) on the topic is not so good. My unde... |
What legal guidelines exist for completeness of a Materials Safety Data Sheet? |
Are there any hueristics to get the relative absorbtion of left and right circularly polarized light by a molecule from it's molecular structure? Is it even possible to obtain which polarization is selectively absorbed? |
Is there a simple way to get the circular dichroism of a molecule from it's structure? |
I'm trying the data or a site that has the spectral analysis of the periodic table of elements in the time domain format. All the sites
I know have the data in the frequency domain which is great but I need to do my own fft analysis starting from the time domain. Does anyone know where I can get this data or can som... |
I'm trying to get the spectral analysis data of the periodic table of elements in the time domain format or find a site that has the data in the **time domain format**. All the sites
I know have the data in the frequency domain which is great but **I need to do my own fft analysis starting from the time domain**. Do... |
I'm trying to get the spectral analysis data of the periodic table of elements in the **time domain format** or find a site that has the data in the **time domain format**. All the sites
I know have the data in the frequency domain which is great but **I need to do my own fft analysis starting from the time domain**.... |
I'm trying to get the spectral analysis data of the periodic table of elements in the **time domain format** or find a site that has the data in the **time domain format**. All the sites
I know have the data in the frequency domain which is great but **I need to do my own fft analysis starting from the time domain be... |
I'm trying to get the spectral analysis data of the periodic table of elements in the **time domain format** or find a site that has the data in the **time domain format**. All the sites
I know have the data in the frequency domain which is great but **I need to do my own fft analysis starting from the time domain be... |
I'm trying to get the spectral analysis data of the periodic table of elements in the **time domain format** or find a site that has the data in the **time domain format**. All the sites
I know have the data in the frequency domain which is great but **I need to do my own fft analysis starting from the time domain be... |
When looking at a Diopside-Hedenbergite solid solution, what is the difference between an ionic and molecular activity model? Why does the moleclar model yield higher values? |
I'd like to preface this with a declaration of my understanding that this is not necessarily possible.
I was wondering if anyone knew of a chemical clock reaction where the period before the first change (the induction period?) is very long (between 3 hours and a day) and the change is à la Landolt or Old Nassau rea... |
**Original question:**
When looking at a Diopside-Hedenbergite solid solution, what is the difference between an ionic and molecular activity model? Why does the moleclar model yield higher values?
**Post-Edit question:**
The two activities calculated below seem to me like I'm just comparing some random values... |
Are there any heuristics to get the relative absorbtion of left and right circularly polarized light by a molecule from its molecular structure? Is it even possible to predict which polarization is selectively absorbed? |
I'm wondering how to properly perturb a quantum mechanical system. Not (_I think_) in the sense of perturbation theory, where one finds a solution to a complex problem by first solving a simpler problem.
I'm looking for a way to express the return to equilibrium of such a perturbed state, where the perturbation is i... |
I'm wondering how to properly perturb a quantum mechanical system.
I'm looking for a way to express the return to equilibrium of such a perturbed state, where the perturbation is in the Hamiltonian. The unperturbed Hamiltonian is $H_{\text{u}}$ and the perturbed Hamiltonian is $H_{\text{p}}$.
I can compute the ei... |
When an electron is added to cesium, why is energy released? |
Why does cesium have a positive electron affinity? |
I was looking at the chemical structure of H<sub>2</sub>SO<sub>4</sub> from http://www.webanswers.com/education/high-school/what-is-the-chemical-symbol-of-sulfuric-acid-23fae0.
![enter image description here][1]
![enter image description here][2]
Intuitively, I would have expected this molecule to be square plan... |
> *Compound 1 was hydrothermally synthesized under autogenous pressure*<sup>[1]</sup>
I've seen this term used a few times, but with no real explanation of what it means forthcoming. I suspect it refers to the synthesis being performed at equilibrium pressure inside a sealed container (the aforementioned synthesis i... |
What is 'autogenous pressure'? |
I was looking at the [chemical structure of H<sub>2</sub>SO<sub>4</sub>](http://www.webanswers.com/education/high-school/what-is-the-chemical-symbol-of-sulfuric-acid-23fae0).
![enter image description here][1]
![enter image description here][2]
Intuitively, I would have expected this molecule to be square planar... |
What is the order of dipole moments of $\small \ce{SO3, SiO2, P2O5,}$ and $\small\ce{ Cl2O7}$? This question is from a book and the answer given is $\small\ce{Cl2O7 < SO3 < P2O5 < SiO2}$. Can someone explain why? When I drew the Lewis Structures and applied VSEPR, it seemed that all the given compounds have zero dipole... |
I am wondering how the cocoate ion (in natural soaps, in the form of sodium or potassium cocoate and from the saponification of coconut oil) differs structurally from the olivate ion (from the saponification of olive oil)?
My family is attempting to implement the methods in solveeczema.org and believe that our child... |
Sorry for the super simple question... Which of the following possesses the highest energy electron?
A) Br<sup>–</sup>
B) Ca<sup>++</sup>
C) Cr<sup>+</sup>
D) As
Don't Bromine and Arsenic have equally high energy electrons (i.e. in the 4p orbital)? My book says that Arsenic is the correct answer (D). But I don... |
I know almost nothing beyond 10th grade chemistry. I'm trying to name a web application, and was wondering what the products are of a reaction between the element Chromium and the gas Ozone (ozonolysis of chromium?). |
I am reading a paper[1] that contains the line:
> Most of the $H_2$ in the Earth's mantle escaped to space early in the Earth's history; consequently, the overwhelming majority of the abiotic geochemical reactions are based on acid/base chemistry, i.e., transfers of protons without electrons.
The connection betw... |
Why would the loss of $H_2$ to space mean that the Earth's geochemistry would be based on acid/base reactions? |
Let us consider the following:
1.) Method X fails at describing intermolecular non-covalent interactions.
2.) Method X excels at describing molecules of type Y.
3.) Method X __________?__________ at describing molecules of type Y_1 containing intramolecular non-covalent interactions.
Is there an existing ge... |
Methods: Does failing at intermolecular properties mean the same for intramolecular properties? |
Let us consider the following:
1.) Method X fails at describing intermolecular non-covalent interactions.
2.) Method X excels at describing molecules of type Y.
3.) Method X __________?__________ at describing molecules of type Y_1 containing intramolecular non-covalent interactions.
Is there an existing ge... |
Let us consider the following:
1.) Method X fails at describing intermolecular non-covalent interactions.
2.) Method X excels at describing molecules of type Y.
3.) Method X __________?__________ at describing molecules of type Y_1 containing intramolecular non-covalent interactions.
Is there an existing ge... |
The fact that the solution turned clear is a pretty good guarantee that this was a redox reaction: the permanganate oxidised some other species, and in turn was reduced, probably to manganese dioxide, the brown precipitate you noticed. Unfortunately, neither of the other reactants you mention are reducing agents!
Do... |
I am reading a paper[1] that contains the line:
> Most of the $\small H_2$ in the Earth's mantle escaped to space early in the Earth's history; consequently, the overwhelming majority of the abiotic geochemical reactions are based on acid/base chemistry, i.e., transfers of protons without electrons.
The connecti... |
Why would the loss of H2 to space mean that the Earth's geochemistry would be based on acid/base reactions? |
In my self-study, I recently came across the following question:
"Choose the solute of each pair that would be more soluble in hexane (C6H14). Explain your answer.
(a) CH3(CH2)10OH or CH3(CH2)2OH ..."
Undecanol is more soluble in hexane because it is apparently less polar than propanol. Further Internet search... |
Why are alcohols with longer chains less polar? |
In my self-study, I recently came across the following question:
"Choose the solute of each pair that would be more soluble in hexane ($\ce{C6H14}$). Explain your answer.
(a) $\ce{CH3(CH2)10OH}$ or $\ce{CH3(CH2)2OH}$ ..."
Undecanol is more soluble in hexane because it is apparently less polar than propanol. Fu... |
**If you're sure that the initial formula is $\ce{H3COOCH3}$** (and that's a big **if**), then I disagree with Richard's answer in comments. [$\ce{H3COOCH3}$ is dimethyl peroxide](http://webbook.nist.gov/cgi/cbook.cgi?ID=C690028&Units=SI). While peroxides are not the most stable of molecules, and decompose rapidly (oft... |
Could a filter be used to isolating salt from sea water? Could we say that the water molecules are smaller than the molecules of salt dissolved in the water. I have no relation to chemistry or physics, so pardon the question if it too naive. Thanks. |
Could a filter be used to isolating salt from sea water? Could we say that the water molecules are smaller than the molecules of salt dissolved in the water. I have no relation to chemistry or physics, so pardon the question if it too naive. |
I'm wondering if someone can help me out with this concept. I've just started Physical Chemistry and it's a bit confusing.
What does the moment of inertia for a molecule mean? How is it useful? Most importantly, how would I go about solving it for a triatomic molecule? |
I tried to find info on tin toxicity but there is not much.
Wikipedia here says that it is not very poisonous:
http://en.wikipedia.org/wiki/Tin_poisoning
but there could be cases.
My question is - is it dangerous to say have a coffee boiled in a tin container? I know that coffee has some acidity, so it can proba... |
Is tin and tinware toxic? |
I tried to find info on tin toxicity but there is not much.
[Wikipedia][1] here says that it is not very poisonous; but there could be cases.
My question is - is it dangerous to say have a coffee boiled in a tin container? I know that coffee has some acidity, so it can probably react with tin.
[1]: http://... |
If we know the properties of two elements e.g Oxygen and Hydrogen.
We know the following properties
- sound speed
- boiling point
- melting point
- refractive index
- etc.
given that information, is it possible to deduce the properties of a compound such as water H2O without resorting to chemical experime... |
> is it possible to deduce the properties of a compound such as water H2O without resorting to chemical experiments?
**Not yet, assuming you mean extrapolating such information from the molecule's structure**
Physical and chemical properties are hard enough to extrapolate from a compound's structure, let along ... |
Are there theoretical reasons for or against the existence of materials that will _not_ become solid at some fixed, sufficiently large temperature when enough pressure is applied? Or is this even the normal state of affairs?
The usual phase diagrams typically only give a finite portion of the thermodynamical state... |
What is known about the phase of matter at very high temperature and enough pressure? |
So we are told that a unimolecular elementary reaction has a rate law of $k[\text{A}]$ where a termolecular reaction with three unique reagents, $A$, $B$ and $C$ has a rate law of $k[\text{A}][\text{B}][\text{C}]$. Now, other things being equal, and assuming for the sake of argument that the initial concentrations are ... |
Why do collisions in elementary reactions of higher-orders appear to be more likely? |
I wonder if the words on my T-shrit are removable? If yes, what kind of (chemical or physical) ways are there?
They look like paints on the cloth, as the letter "C" has become blurred in the way shown in the picture over the time when I was wearing it. But I admit that I don't know anything about how words are prin... |
Are words on my T-shrit removable? |
I wonder if the words on my T-shirt are removable? If yes, what kind of (chemical or physical) ways are there?
They look like paints on the cloth, as the letter "C" has become blurred in the way shown in the picture over the time when I was wearing it. But I admit that I don't know anything about how words are prin... |
Are words on my T-shirt removable? |
> I guess that an alternative way of asking this question is what is the
> hybridization of H2SO4?
A better way to ask this might be: "What is the hybridization of the sulfur atom in Hydrogen Sulfate?"
The sulfur atom has a bond with four other atoms in this molecule. Because that the electrons try to stay as fa... |
As you say, it appears to be a kind of paint? So perhaps if you get a razor or something sharp you could try scraping and it will probably come off eventually, that would be one physical way. On the other hand if you want to go crazy try putting some paint thinner on there and see what happens, but don't blame me if yo... |
As you say, it appears to be a kind of paint? So perhaps if you get a razor or something sharp you could try scraping and it will probably come off eventually, that would be one physical way. On the other hand if you want to go crazy try putting some paint thinner on there and see what happens, but don't blame me if yo... |
For yellow rings on shirts caused by skin grease or sweat:
- Some recommended to use Oxyclean stain remover or stain remover stick
for cleaning.
- Some recommended to use dishwashing detergent to brush and wash the
stains, saying "dish washing liquid is designed to remove grease, and
why buy another p... |
Are dishwashing detergent and stain remover powder/stick having the similar ability to remove collar yellow rings? |
For yellow rings on shirts caused by skin grease or sweat:
- Some recommended to use an "Oxyclean" stain remover or stain remover stick
for cleaning.
- Some recommended to use dishwashing detergent to brush and wash the
stains, saying "dish washing liquid is designed to remove grease, and
why buy anot... |
Do dishwashing detergent and stain remover powder/stick have the similar ability to remove collar rings? |
> I guess that an alternative way of asking this question is what is the
> hybridization of H2SO4?
A better way to ask this might be: "What is the hybridization of the sulfur atom in Hydrogen Sulfate?"
The sulfur atom has a bond with four other atoms in this molecule. Because that the electrons try to stay as fa... |
Take an ice cube for example. Heat is applied in a closed container until it is vaporized completely. Will the molecule's size be larger (on average)? Is there a substance that you know of that has odd behaviour such as changing size due to temperature change? Obviously there would be more pressure in the case of $H_2O... |
Is there any scenario in which the size of a molecule increases due to an increase in temperature? |
Take an ice cube for example. Heat is applied in a closed container until it is vaporized completely. Will the molecule's size be larger (on average)? Is there a substance that you know of that has odd behaviour such as changing molecular size due to temperature change? Obviously there would be more pressure in the cas... |
For yellow rings on shirts caused by skin grease or sweat:
- Some recommended to use an "Oxyclean" stain remover or stain remover stick
for cleaning.
- Some recommended to use dishwashing detergent to brush and wash the
stains, saying "dish washing liquid is designed to remove grease, and
why buy anot... |
This might seem like a ridiculous question. I was drinking some tea, and I randomly decided to pour some into the toilet in an unbroken fashion. How fast can diffusion occur? Can particles travel "upsteam" quickly enough? What if I pour it into highly concentrated toxic waste? It is, after all, a continuous functi... |
The equation for the reaction between permanganate and iron(II) ions in **acidic** solution:
$MnO_4^- + Fe^{2+} + ==> Fe^{3+} + Mn^{2+}$
My book, as well as a certain [equation balancer][1] show that the answer is:
$5Fe^{2+} + MnO_4^- + 8H^+ ==> 5Fe^{3+} + Mn^{2+} + 4H_2O$
They check to ensure that it is in... |
Do you know an alternative to the half-reaction method to solving red-ox reactions? |
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