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Chemical synthesis via 3D printing? |
I will be using trimethyl tin chloride (1M in THF) in a few days for the first time. Looking at the MSDS, it looks like it is very toxic and has noxious vapors. Are there any more standard precautions for working with it other than the usual?
E.g.,
- Check for proper airflow in the hood
- Wear lab coat, safety... |
When a piece of cast iron is repeatedly covered in fat and exposed to heat it develops a hard, black, non-stick coating referred to as "seasoning".
What exactly is this coating made of molecularly? How is it bonded to the cast iron substrate? What is the chemical process that transforms a liquid fat into this coatin... |
What is the molecular structure of the coating on cast iron cookware known as seasoning? |
So called food grade stuff is meant to be consumed by humans. It's important that every single compound of a foodstuff is food grade or at least [GRAS][1]. In the European Union the law giver has defined the state when a compound is good for consumption as "save".
Lab grade chemicals often contain toxic materials, s... |
I have a number of [Chemical Table files](http://en.wikipedia.org/wiki/Chemical_table_file) which include a ["M ZZE" tag in the properties block](http://pastebin.com/cPg2p7GZ).
For example, in [Galactobuxin](http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=85296601), I have:
`M ZZE 1 31 23`
In [Rub... |
The authors use a **3D printer** to generate the labware, and to place the reagents in its inlets.
So we're not printing standard ink on paper but using a the *print head* to exactly place very amounts of monomers at certain positions. These monomers cure (polymerize) upon heat or irradiation to a solid resin. By th... |
Can nanotechnology reduce electrode losses in electrochemical cells? |
I did a short experiment in which I connected a 1.5v battery with 2 paper clips into a bowl of water. After a while, I saw a yellowish-greenish cloud inside the water around one of the paper clips, and when I took it out, the part that was in the water was more black than the rest of the paper clip. After a while, some... |
I did a short experiment in which I connected a 1.5v battery with 2 paper clips into a bowl of water to which I added salt. After a while, I saw a yellowish-greenish cloud inside the water around one of the paper clips, and when I took it out, the part that was in the water was more black than the rest of the paper cli... |
I plan on etching some PCBs with hydrochloric acid and hydrogen peroxide, which will therefore produce some kind of copper chloride (green color) which is highly toxic if released into the environnement (it may be useful as an herbicide, but I don't have any garden right now).
While cupric acid (obtained from hydroc... |
I always hear that some big corporations use "diamond dust" to filter water seven times to make "diamond clear" vodka. I tried googling something about using diamonds for filtering, but I could not find anything except corporate sites that tell us only the best things about "diamond dust filtration technology".
Is t... |
I recently was told that once you find a good solvent mixture for separation on [thin layer chromatography][1] (TLC), you should only use 10% of the more polar solvent (for silica) when you run your column. I tried it and it worked great!
Since I'd never heard that before, is that a standard rule of thumb, or did I... |
How to translate the mobile phase from thin layer chromatography to column? |
Is radiation time the same thing as half life period?
Also, if I'm talking about excited species in a gas, how would the gas interaction affect the radiation time, are there some formulas/approaches? |
The motivation for the question in the title is that I have some formula given,
$$\Delta T=\frac{3410\ \gamma_{O_2}}{2.5+\gamma_{O_2}},$$
where $\gamma_{O_2}$ is the molar fraction of oxygen in a binary micture and the ratio of oxygen and rate gas heat capacities are supposed to be 7.5, if that helps. And there i... |
How can I compute the temperature change from the de-excitation of excited particle species? |
Altered properties (band gap, Stokes shift) of cristalline nanoparticles as compared to bulk have been demonstated for various semiconductors, namely CdS, CdSe, TiO<sub>2</sub>, etc. They result from a significantly different surface-to-volume ratio and the fact that atoms at the crystal surfaces simply lack the proper... |
What I think you are asking about is the number of thermodynamic parameters which characterize a chemical reaction. Those parameters are used to make **quantitative predictions** of the final state of the reactive system (at least in the context I'm familiar with, i.e. chemical engineering); for example, the amount of ... |
What I think you are asking about is the number of thermodynamic parameters which characterize a chemical reaction. Those parameters are used to make **quantitative predictions** of the final state of the reactive system (at least in the context I'm familiar with, i.e. chemical engineering); for example, the amount of ... |
What I think you are asking about is the number of thermodynamic parameters which characterize a chemical reaction. Those parameters are used to make **quantitative predictions** of the final state of the reactive system (at least in the context I'm familiar with, i.e. chemical engineering); for example, the amount of ... |
What I think you are asking about is the number of thermodynamic parameters which characterize a chemical reaction. Those parameters are used to make **quantitative predictions** of the final state of the reactive system (at least in the context I'm familiar with, i.e. chemical engineering); for example, the amount of ... |
What I think you are asking about is the number of thermodynamic parameters which characterize a chemical reaction. Those parameters are used to make **quantitative predictions** of the final state of the reactive system (at least in the context I'm familiar with, i.e. chemical engineering); for example, the amount of ... |
I am an artist attempting to use [Tollen's Reagent][1] in a number of my projects. Is there any reason I could not substitute Copper Nitrate for the Silver Nitrate in the reaction? Would the copper adhere to the glass? Thanks
[1]: http://en.wikipedia.org/wiki/Tollens%27_reagent |
Altered properties (band gap, Stokes shift) of cristalline nanoparticles as compared to bulk have been demonstated for various semiconductors, namely CdS, CdSe, TiO<sub>2</sub>, etc. They result from a significantly different surface-to-volume ratio and the fact that atoms at the crystal surfaces simply lack the proper... |
Unfortunately, I don't have batteries to waste to test this myself, but I am curious...
Let's say you have two identical batteries. AA Duracell.
Now let's say you run one of the batteries through an LED until the LED starts emitting at half the intensity it was emitting at when you first started (effectively d... |
Michael Faraday melted sodium chloride in a silver spoon and ran an electric current through the molten salt, which released the chlorine as gas and left the pure sodium behind.
Sodium chloride melts at 800 C. How did Michael Faraday melt the salt?
*I know he invented the bunsen burner, but did he use that? |
How Did Michael Faraday Melt Sodium Chloride? |
Michael Faraday melted sodium chloride in a silver spoon and ran an electric current through the molten salt, which released chlorine as a gas and left pure sodium behind.
Sodium chloride melts at 800 C. How did Michael Faraday melt the salt?
*I know he invented the bunsen burner, but did he use that? |
How did Michael Faraday melt Sodium Chloride? |
I am an artist attempting to use [Tollen's Reagent][1] in a number of my projects.
Is there any reason I could not substitute Copper Nitrate for the Silver Nitrate in the reaction? Would the copper adhere to the glass?
[1]: http://en.wikipedia.org/wiki/Tollens%27_reagent |
In certain applications some sorts of stainless steel `(V2A, 1.4301)` corrode when exposed to $\small{Cl^-}$ in water, or at least it is strongly advised to use other steels.
The conditions that were explained to me as being especially bad were: redox potential >0, acidic environment.
Under these conditions, why ... |
Why does Chloride attack CrO? |
PEP (Phosphoenolpyruvic acid) is acidic but I need to make it neutral. I need a solution(pH 6-8) of PEP in a final 1mL volume with a concentration of 100mM. How would I make this? |
How would I make this solution? |
From the school time I remember the very important rule: the first you need to pour water and then acid (when need to mix them) not otherwise. This is because otherwise the aсid becomes very hot and splashing may happen. So, why it gets hot when water is poured into it? What reaction takes place?
|
Why first water and then acid? |
What would happen if I added Na$_2$CO$_3 \cdot n$(H$_2$O) to a solution of HCl? Could I consider the reaction the same as just Na$_2$CO$_3$ + HCl $\to$ NaCl + CO$_2$ + H$_2$O? |
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... |
What is the chemical structure of the cocoate ion vs. the olivate ion? |
What are the different diagrams/tables used to organize the elements other than the Periodic Table? What are the advantages/disadvantages of each? |
What are alternates to the Periodic Table of the Elements? |
What is the bandgap value of SiO2? |
most Lipids in a cell have ester bonds(made up of glycerol and fatty acids).
![enter image description here][1]
I have learn in my chemistry class that we can hydrolysis an ester compound by simply adding water to it.
![enter image description here][2]
Then why lipids which have an ester bond doesnt hydrol... |
One can generate molecular orbitals (MO) from a linear combination of atomic orbitals (LCAO). Let's generate our MOs with the Hückel method, since it's so easy.
**Ethylene**
Ethylene ($\ce{C2H4}$) has 2 pi electrons and is linear. Its Hückel MOs are:
$$\psi_1 = \frac{1}{\sqrt{2}}(\phi_1 + \phi_2)$$
$$\psi_1 =... |
Most Lipids in a cell have ester bonds (made up of glycerol and fatty acids).
![enter image description here][1]
I have learned in my chemistry class that we can hydrolyze an ester by simply adding water to it.
$$\cee{CH3COOCH2CH3 + H2O <=>[H^+ (aq)] CH3COOH + EtOH}$$
Then why do lipids which have an... |
Why do lipids in a cell hydrolyze into glycerol and fatty acids? |
Most Lipids in a cell have ester bonds (made up of glycerol and fatty acids).
![enter image description here][1]
I have learned in my chemistry class that we can hydrolyze an ester by simply adding water to it.
$$\cee{CH3COOCH2CH3 + H2O <=>[H^+ (aq)] CH3COOH + EtOH}$$
Then why do lipids which have an... |
I've seen it many times... Why does the solid-like soap becomes like a foam when it reacts with water (moisture) or when we touch it with wet hands.. What compound formed actually cause this physical change? |
_The previous question contained too much unnecessary information and was edited._
I am wondering about the "hierarchy" of wavefunctions. If one can combine atomic orbitals (AO) into molecular orbitals (MO) through the LCAO method, could one combine MOs to form a _supra_ wavefunction, or an LCMO?
I've done some r... |
Can you tell me what is a burst nucleation process, and how can it be used for synthesising uniform nanoparticles?
Can you also provide (if possible) any links to papers or materials regarding mechanism of nanoparticles growth?
|
What is burst nucleation? |
How to convert CO2 into Carbon and Oxygen?
CO2 --> C + O2
Alternatively:
CO2 + ? --> C? + O2
I know that plants are able to do this but I am wondering if I can also do this without them. I didn't try anything yet, because I have no idea where to start. I did search Google though. |
How to convert CO2 into Carbon and Oxygen? |
How to convert $\small\ce{CO2}$ into Carbon and Oxygen?
$\cf{CO2 -> C + O2}$
Alternatively:
$\cf{CO2 + ? -> C? + O2}$
I know that plants are able to do this but I am wondering if I can also do this without them. |
For the purposes of x-ray absorption, I'm trying to discover the average chemical composition of a typical PCB.
My research so far has indicated that the most common type of PCB is designated FR-4. It is composed of fiberglass and epoxy resin. The resin often contain Bromine to add fire resistance. Let's ignore a... |
Composition of a typical printed circuit board (PCB)? |
How can convert $\small\ce{CO2}$ into Carbon and Oxygen?
$\cf{CO2 -> C + O2}$
Alternatively:
$\cf{CO2 + ? -> C? + O2}$
I know that plants are able to do this but I am wondering if I can also do this without using plants. |
What is the order of dipole moments of SO3, SiO2, P2O5, and CL2O7? This question is from a book and the answer given is 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 moment. |
Consider a chemical reaction where two different particles form another one
$$O+O_2\rightarrow O_3.$$
I find it confusing how this can be an exothermic process. How to picture the release of $+\Delta H$ to the surroundings.
And am I right in viewing this energy value only as the net energy coming from an int... |
What is the energy package released to the outside world? |
I've seen it many times... Why does soap becomes like a foam when it reacts with water (moisture) or when we touch it with wet hands.. What compound formed actually cause this physical change and why is this change in its physical form? |
I've seen it many times... Why does the solid-like soap becomes like a foam when it reacts with water (moisture) or when we touch it with wet hands.. What compound formed actually cause this physical change? |
I've seen it many times... Why does soap becomes like a foam when it reacts with water (moisture) or when we touch it with wet hands.. What compound formed actually cause this physical change? And why is this physical change? |
I wonder, what software packs / environments are available for chemical reaction simulation. The goal is to learn or just rehearse some basic knowledge in chemistry. I suppose there should be some to buy but are there any open source projects dedicated to this? |
The "packet" of energy exchanged fall into one of three forms: heat, work, or electromagnetic radiation. The first two are kinetic energy phenomena.
Expanding on [Aesin's answer][1] about potential and kinetic energy.
Reactions that are exothermic convert potential energy into kinetic energy. The potential energ... |
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... |
What is the order of dipole moments of $\ce{SO3, SiO2, P2O5,}$ and $\ce{ Cl2O7}$? This question is from a book and the answer given is $\ce{Cl2O7 < SO3 < P2O5 < SiO2}$. Can someone explain why? When I drew the Lewis Structures and applied VSEPR, it seemed that all the given compounds have zero dipole moment. |
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... |
This may be a stupidly simple question, but as I've only completed an introductory course in chemistry, please answer kindly.
I was drawing out all the isomers of C2H8 and came upon two structures of cyclopropane attached with double bonds. The group is neither a methylene nor an ethyl... what is it? What are the na... |
What is the name of cyclopropane with a double bond? |
This may be a stupidly simple question, but as I've only completed an introductory course in chemistry, please answer kindly.
I was drawing out all the isomers of $\ce{C5H8}$ and came upon two structures of cyclopropane attached with double bonds. The group is neither a methylene nor an ethyl... what is it? What are... |
I was drawing out all the isomers of $\ce{C5H8}$ and came upon two structures of cyclopropane attached with double bonds. The group is neither a methylene nor an ethyl... what is it? What are the names of these two molecules?
![Images][1]
[1]: http://farm9.staticflickr.com/8298/7744615572_324b36e842_z.j... |
I'm calculating molar changes in thermodynamic properties due to reactions between gasses (assumed to be ideal gases). I can calculate $\Delta H$ easily enough, because it's just $\sum_i \nu_i\Delta_f H^\circ_i$, with $\nu_i$ the stoichiometric coefficients. $\Delta G$ (at standard pressure) can be calculated from $\s... |
How to calculate entropy change for a gas reaction using $S^\circ$? |
I was reading up on a wonderful little chemical compound known as chlorine trifluoride (ClF<sub>3</sub>). For a primer, check out Dr. Derek Lowe's blog post here: [Sand Won't Save You This Time][1]. The title of the post is quite telling; this compound is so reactive with other compounds - any other compound, really - ... |
How can $\small\cf{CO2}$ be converted into Carbon and Oxygen?
$\cf{CO2 -> C + O2}$
Alternatively:
$\cf{CO2 + ? -> C + O2}$
I know that plants are able to do this. But I'm wondering if it can be done without using plants? |
How to convert Carbon dioxide into Carbon and Oxygen? |
I'm working on a program that needs to determine if a bond between two or more elements will result in a stable state. I understand at a high-level how to fill electron subshells using the Aufbau principle, but I also read that in some cases, electrons will jump from a lower energy shell or orbital to a higher one in ... |
How to determine stable electron states in ionic and covalent bonds? |
Just to make sure that I get your question correctly; the process in question is a chemical reaction that takes place at a temperature and pressure close enough to the reference temperature and pressure (those used for the tabulated values) that any changes to the tabulated values are neglible? (I assume this, as this ... |
I'm working on a program that needs to determine if a bond between two or more elements will result in a stable state. I understand at a high-level how to fill electron subshells using the Aufbau principle, but I also read that in some cases, electrons will jump from a lower energy shell or orbital to a higher one in ... |
As I was doing my Ap Chem homework, sometimes the question would use Iron(III) and sometimes it would use Ferric. What's the difference in usage? Also, what's the difference between Iron(II) and Ferrous? |
What's the difference between bisulfate and "something" hydrogen sulfate? It seems like there is a rule for these things, but I don't seem to get it |
What's the difference between bisulfate and "something" hydrogen sulfate?
Has there historically been a preference for one over the other? |
How would I neutralize a Phosphoenolpyruvic acid? |
##Problem:##
On my boat I have a marine toilet. It is operated with salt water.
The problem is, on the interior of the outflow tubing it accumulates some sort of hard grime. I am looking for a good way to dissolve this grime as it is impossible to replace the tubing.
From experience it is known that citric aci... |
##Problem:##
On my boat I have a marine toilet. It is operated with salt water.
The problem is, on the interior of the outflow tubing it accumulates some sort of hard grime. I am looking for a good way to dissolve this grime as it is impossible to replace the tubing.
From experience it is known that citric aci... |
From [an article in the New Scientist in 2010][1],
> Since pre-industrial times, methane levels in the atmosphere have risen from around 715 parts per billion to nearly 1800 ppb, claims Folberth. "If methane could be taken back to pre-industrial levels it would bring about half a degree of cooling and would be equ... |
What chemicals could absorb/adsorb ambient atmospheric methane? |
There is no. Alkanes are very hard to activate. This requires either free radicals, or coordinately unsaturated sites either in molecule or on surface of solid. But in both cases, the atmosphere contains molecules, that will react more readily.
However, net life-time of methane in atmosphere is quite small, less the... |
I'm given a flow rate of of a gas mixture of $3\ Nm^3/h$ in [standard cubic meters](http://en.wikipedia.org/wiki/Standard_cubic_foot) through a cylinder of length $50\ cm$ and cross section $70\ cm^2$, can I compute how long a particle will stay inside of the cylinder (which would equal the time the particle can react ... |
How to compute the residence time for given flow rate in standard cubic meters? |
I watched a video on the construction of [Burj Khalifa](http://en.wikipedia.org/wiki/Burj_Khalifa), Dubai. The construction engineers answered that they're using a special type of protection known as [Cathodic protection](http://en.wikipedia.org/wiki/Cathodic_protection) to protect from the corrosion due to local groun... |
I watched a video on the construction of [Burj Khalifa](http://en.wikipedia.org/wiki/Burj_Khalifa), Dubai. The construction engineers answered that they're using a special type of protection known as [Cathodic protection](http://en.wikipedia.org/wiki/Cathodic_protection) to protect from the corrosion due to local groun... |
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 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 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... |
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... |
Why is methane's molecular formula conventionally "CH4", while water is "H20" (among others)? |
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