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Many of the chemicals used in metal plating are extremely poisonous (cyanide), cause severe allergies (Ni), and are carcinogenic (Cr(VI)).
I'd consider it as extremely unprofessional (besides violating many laws and regulations), to re-use anything that has been in contact with these materials for any purpose that r... |
While doing computational chemistry for both organic and inorganic compounds we will do energy optimization of that compound before starting a study.
For example, if we do drug docking studies using aspirin, first we will make aspirin chemical struture and then we will optimize it. So what does "energy optimization"... |
While doing computational chemistry for both organic and inorganic compounds, an energy optimization of that compound is done before starting a study.
For example, if we do drug docking studies using aspirin, first we would make aspirin's chemical structure, and then we would optimize it. So what does "energy optimi... |
What is in silico energy optimization? |
What do you call the proton in a C<b>H</b>-OH configuration? When discussing an NMR spectrum, I can talk about the hydroxyl proton, but it seems clumsy to refer to "the proton on the hydroxyl carbon". |
When we calculate the electrons and orbital numbers in $\ce{CH4}$ $sp^3$ hybridization we have taken 3 electrons from $2p$ of $\ce{C}$ and 1 electron from $2s$ of $\ce{C}$ but in $\ce{C2H4}$ we have $2sp^2$ (2 electrons from $2p$ and 1 from $2s$).
1. Why do $\ce{C}$'s atomic orbitals make $2sp^2$ in $\ce{C2H4}$ and ... |
What do you call the proton in a C<b>H</b>-OH configuration?
When discussing an NMR spectrum, I can talk about the hydroxyl proton, but it seems clumsy to refer to "the proton on the hydroxyl carbon". |
Why are some salt solutions coloured? |
A Koppers-Totzek reactor (there seems to be only [a German Wikipedia page][1]) is an entrained flow gasifier that blows coal dust, oxygen and water into a burning chamber where the coal burns at about 1600 °C. The output contains around 60% CO and 33% H2, plus some CO2 and CH4.
When burning coal, I would expect CO2 ... |
In a Koppers-Totzek reactor, why do I get CO and H2 instead of CO2 and H2O? |
You're right--it's got to do with them being transition metals (usually). Transition metal ions form [coordination complexes][1]. Their empty $d$ orbitals accept lone pairs from other molecules (called "ligands") and form larger molecules (though we don't call them that--we call them "complexes"). When put in water, th... |
You're right--it's got to do with them being transition metals (usually). Transition metal ions form [coordination complexes][1]. Their empty $d$ orbitals accept lone pairs from other molecules (called "ligands") and form larger molecules (though we don't call them that--we call them "complexes"). When put in water, th... |
A Koppers-Totzek reactor (there seems to be only [a German Wikipedia page][1]) is an entrained flow gasifier that blows coal dust, oxygen and water into a burning chamber where the coal burns at about 1600 °C. The output contains around 60% $\ce{CO}$ and 33% $\ce{H2}$, plus some $\ce{CO2}$ and $\ce{CH4}$.
When burni... |
In a Koppers-Totzek reactor, why do I get CO and H₂ instead of CO₂ and H₂O? |
A Koppers-Totzek reactor (there seems to be only [a German Wikipedia page][1]) is an entrained flow gasifier that blows coal dust, oxygen and water (as steam, of course) into a burning chamber where the coal burns at about 1600 °C. The output contains around 60% $\ce{CO}$ and 33% $\ce{H2}$, plus some $\ce{CO2}$ and (ve... |
I'm no chemist, but even though this should probably be obvious to me, I'm still unsure. If we were trying to figure out the time scale for a gas-phase reaction between two hydrogen atoms in a molecular cloud (which has density $~10^4/$cm$^3$), apparently the reaction would happen on a time scale proportional to the in... |
Why does $H_2$ form on such a long time scale? |
I'm no chemist, but even though this should probably be obvious to me, I'm still unsure. If we were trying to figure out the time scale for a gas-phase reaction between two hydrogen atoms in a molecular cloud (which has density $~10^4/$cm$^3$), apparently the reaction would happen on a time scale proportional to the in... |
Why does H₂ form on such a long time scale? |
I'm no chemist, but even though this should probably be obvious to me, I'm still unsure. If we were trying to figure out the time scale for a gas-phase reaction between two hydrogen atoms in a molecular cloud (which has density $~10^4/$cm$^3$), apparently the reaction would happen on a time scale proportional to the in... |
> Why is the time-scale so long?
The time-scale is so long because the density is not just low, it's virtually nonexistent.
The particle density of any gas can be determined at any temperature and pressure using the ideal gas law (PV=nRT). Let's use air as an example. At 25 <sup>o</sup>C (298 K), and 1 atmosphere... |
Why are there no edge dislocations in a face-centered cubic (FCC) lattice? |
I understand why smaller particles have more velocity, but I don't understand what velocity has to do with rate of effusion:
My reasoning is thus:
1. Pressure is the number of impacts of particles in a given period of time.
2. If He and Ar are both in balloons at, say, 1.5 atm, both gasses have the same aver... |
Why does molecular mass affect rate of effusion? |
Why does gas particle velocity affect rate of effusion? |
Sodium Perborate is a well known bleaching agent in detergents. What makes Sodium Perborate an effective bleeching agent and how is this related to it's oxidation chemistry? |
Sodium Perborate is a well known bleaching agent in detergents. What makes Sodium Perborate an effective bleaching agent and how is this related to its oxidation chemistry? |
I prepared a compound "SO2-Quinolclathrate" by dissolving hydroquinone and sodium sulfite with hydrochloric acid in water. (warm water).
After this I tested a little sample of the product on flame and a gaseous was vaporized and smelled. I am supposed to define this gaseous and my prediction is that this could be SO2... |
The apparatus that I am using is a glass container,two electrodes,two glass cylinder,and water,battery. In the glass container I will be filling water and two electrodes kept inside the glass cylinder and then it is dipped in water. The two electrodes is then connected with the positive and negative terminal of the bat... |
I prepared a compound "$\ce{SO2}$-Quinolclathrate" by dissolving hydroquinone and sodium sulfite with hydrochloric acid in warm water.
After this, I tested a little sample of the product on a flame and it vaporised, following which I smelled the gas. I am supposed to define this gas and my prediction is that this c... |
I prepared a compound "$\ce{SO2}$-Quinolclathrate" by dissolving hydroquinone and sodium sulfite with hydrochloric acid in warm water.
After this, I tested a little sample of the product on a flame and it vaporised, following which I smelled the gas. I am supposed to define this gas and my prediction is that this c... |
The apparatus that I am using is a glass container, with two electrodes,two glass cylinders, water, and a battery. In the glass container will be filled with water and two electrodes kept inside the glass cylinder and then dipped in water.
The two electrodes are then connected with the positive and negative termina... |
Has anyone come across a scientific study of the S-Plasma Ions that Samsung claims will purify air from microbes, allergens and free radicals? I would prefer publicly available research findings.
The following is a quote from <http://www.samsungspi.com>:
> The Samsung SPi generates Hydrogen atom (H+) and Oxygen ion... |
Has anyone come across a scientific study of the S-Plasma Ions that Samsung claims will purify air from microbes, allergens and free radicals? I would prefer publicly available research findings.
The following is a quote from <http://www.samsungspi.com>:
> The Samsung SPi generates Hydrogen atom (H+) and Oxygen ion... |
Has anyone come across a scientific study of the S-Plasma Ions that Samsung claims will purify air from microbes, allergens and free radicals? I would prefer publicly available research findings.
The following is a quote from <http://www.samsungspi.com>:
> The Samsung SPi generates Hydrogen atom ($\ce{H+}$) and Oxy... |
I'm doing a basic chemistry course, and we are currently learning how to compute $\text{pH}$ from the acid dissociation constant (using $\left[\text{H}^{+}_{(\text{aq})}\right]=\sqrt{K_{a}\left[\text{HA}_{(\text{aq})}\right]}$) along with computing the $\text{pH}$ of strong bases by assuming full dissociation into $\te... |
What is the IUPAC naming of alkane with higher C atoms (more than 200)? Example, what is the IUPAC naming of $C_{205}H_{412}$? |
What is the IUPAC naming of alkane with higher C atoms (more than 200)? |
I know it sounds extremely expensive, but what if we could heat the ionic compound to evaporate it and achieve the lattice energy and break them into free ions, wouldn't be the electrolysis faster as the ions can move faster freely than in liquid state?(sorry if the tags are wrong as i am knew to the site) |
Can the electrolytes be in gaseous state? |
I know it sounds extremely expensive, but what if we could heat the ionic compound to evaporate it and achieve the lattice energy and break them into free ions, wouldn't the electrolysis be faster, as the ions can move faster freely than in liquid state? |
People said that wine is good for health. So I take a cup ( < 100cc ) of wine every evening. (Yes, wine is cheap where I live.) So to finish a bottle of wine (750 cc), it takes me a week.
(Of course I put it in the refrigerator.) I have to say that it doesn't taste good after 3 days (but still OK).
But I don't kno... |
People said that wine is good for health. So I take a cup (less than 100 mL) of wine every evening. (Yes, wine is cheap where I live.) So to finish a bottle of wine (750 mL), it takes me a week.
(Of course I put it in the refrigerator.) I have to say that it doesn't taste good after 3 days (but still OK).
But I don... |
Usually two separate p orbitals would have '4 sides' while in a sp2 hybrid those 2 p orbitals would only have '3 sides'. why? |
In sp2 hybrid orbital, why does the p orbitals only have 3 sides instead of 4? |
If someone were to pour about 5 ml of 94% pure ethanol on a flat surface and at room temperature, approximately how much time would it take for it to evaporate?
|
How long does it take for a thin layer of ethanol to evaporate? |
I knew while learning about electrolysis that if the ionic compound is molten it becomes free moving ions.
If that is the case, what will happen if I continued heating till it reaches the boiling point so that the ionic compound evaporates?
Will it still be free moving ions?
Also, shouldn't the result be more... |
> **Possible Duplicate:**
> [Will gaseous ionic compounds be free moving ions?](http://chemistry.stackexchange.com/questions/2511/will-gaseous-ionic-compounds-be-free-moving-ions)
<!-- End of automatically inserted text -->
I know it sounds extremely expensive, but what if we could heat the ionic compound to evap... |
According to Pauli’s exclusion principle, $s$ orbital contains at most two electrons with the opposite spin(up and down). Why can't $s$ orbital contain a third electron whose state is the linear combination of spin up and down? |
What is the IUPAC nomenclature of alkane with higher C atoms (more than 200)? Example, what is the IUPAC nomenclature of $C_{205}H_{412}$? |
What is the IUPAC nomenclature of alkane with higher C atoms (more than 200)? |
If someone were to pour about 5 ml of 94% pure ethanol on a flat surface and at room temperature, approximately how much time would it take for it to evaporate?
EDIT: In others words, it is to know approximately how much time it would take for a small amount (about 5 ml) of pure alcohol to evaporate if poured over a... |
According to Pauli’s exclusion principle, an $s$ orbital contains at most two electrons with the opposite spin (up and down). Why can't an $s$ orbital contain a third electron whose state is the linear combination of spin up and down? |
Usually two separate p orbitals would have '4 lobes' while in a sp2 hybrid those 2 p orbitals would only have '3 lobes'. why?
I'm referring to diagrams such as the one shown below:
https://i.stack.imgur.com/Cb74T.gif |
Usually two separate p orbitals would have '4 lobes' while in a sp2 hybrid those 2 p orbitals would only have '3 lobes'. why?
I'm referring to diagrams such as the one shown below:
![https://i.stack.imgur.com/Cb74T.gif][1]
[1]: https://i.stack.imgur.com/PZFYn.gif |
I am trying to figure out the configuration for this chiral carbon to answer a homework question, however they arbitrarily include a "D" group as shown in the image. My guess is that it is some higher priority group than the carbon, and lower priority than the halide, making the configuration (S). Is this correct? What... |
What does the "D" group represent on a chiral center? |
If I have a complete Silicon Nitride ball bearing unit, is it safe to hold without any protection? If it cracks, or disintegrates is it also safe? |
Silicon nitride ceramic safe to hold without protection? |
I am not certain that it is safe, but where are you getting the idea that it might be unsafe to touch? Certainly if a powder or mist is appearing if it disintegrates it would probably make sense to avoid inhalation, right? Or if it appears to produce sharp edges that would be another reason to not handle it without pro... |
I have done a minimal amount of research to try and help you understand this material. The credibility of this research is very debatable, as it basically involves me typing in silicon nitride into YouTube. That being said, understand that silicon nitride is first of all extremely strong, [inert][1], according to that ... |
Often the key with stopping the conduction of heat is to provide as many phase transitions as possible. Most thermal insulators achieve this by having voids of Air which is achieved in a variety of ways, bubble wrap, fibre glass etc.
For a "non comercial" I assume they mean stuff you have lying around the lab?
To... |
>Why should they make also an antibonding molecular orbital?
Orbital symmetry must be conserved. Thus, when you mix orbitals, [the number of orbitals must also be conserved][1]. As a consequence, when two orbitals are operated on to produce new orbitals, two new orbitals must be created.
Think about it conceptua... |
I am reading up on how galvanic cell works and I realised that the flow of electron is from Zn to Cu. But Zn is more electronegative compared to Cu according to periodic table trends
I read it somewhere that when comparing transition metals, it may be different, but it was not further elaborated. Can someone explai... |
I was looking up silica gel beads on wiki and noticed that some (and from experience most) are doped with a colouring agent to indicate that they have absorbed all that they can.
The wiki page (http://en.wikipedia.org/wiki/Silica_gel (under Hazards & Moisture indicators)) says that usually Cobalt (II) chloride or M... |
How dangerous is Cobalt (II) Chloride used in silica gel balls? |
I was looking up silica gel beads on wiki and noticed that some (and from experience most) are doped with a colouring agent to indicate that they have absorbed all that they can.
The [wiki page][1] says that usually Cobalt (II) chloride or Methyl violet is used, both of which are toxic. But it mentions nothing abou... |
I am reading up on how galvanic cell works and I realised that the flow of electrons is from Zn to Cu. But Zn is more electronegative compared to Cu according to periodic table trends
I read it somewhere that when comparing transition metals, it may be different, but it was not further elaborated. Can someone expla... |
There are two common confusions in your question. I hope I can clear them up.
>Electrons are not flowing from zinc to copper. Not exactly.
In the Zinc-Copper galvanic cell, the net reaction is:
$$\ce{Zn(s) + Cu}^{2+} (aq) \ce{-> Zn}^{2+} (aq)\ce{ + Cu(s)}$$
Zinc is being oxidized:
$$\ce{Zn(s)->Zn}^{2+}... |
Simple question, the average neutral copper atom has 2 valance electrons, and Sulfide 6. Wouldn't the two electrons jump from copper and bind to sulfide?
The empirical formula is : Cu + S -> Cu2S.
So apparently two copper atoms binds with every one sulfide atom. Does that mean that the copper atoms each gives one... |
If Copper has 2 valance electrons and Sulfide 6, Why dont they bind in pairs? |
Simple question, the average neutral copper atom has 2 valance electrons, and Sulfide 6. Wouldn't the two electrons jump from copper and bind to sulfide?
The empirical formula is : $\ce{Cu + S -> Cu2S}$.
So apparently two copper atoms bind with every one sulfide atom. Does that mean that the copper atoms each giv... |
In my lecture notes for inorganic chemistry, it is stated that magnesium has high affinity for oxygen but is rather stable at room temperature in air.
Anyone can explain why is this so?
Thanks in advance |
Is there anything special about (S)-3-hydroxypalmitoyl-CoA comparing to those with different number of carbons, e.g. (S)-3-hydroxyoctanoyl-CoA, (S)-3-hydroxydecanoyl-CoA, (S)-3-hydroxylauroyl-CoA?
I am not a chemist at all, I am looking at the ChEBI ontology (http://www.ebi.ac.uk/chebi) and wondering why (S)-3-hydr... |
Is (S)-3-hydroxypalmitoyl-CoA a hydroxy fatty acyl-CoA? |
Is there anything special about (S)-3-hydroxypalmitoyl-CoA comparing to those with different number of carbons, e.g. (S)-3-hydroxyoctanoyl-CoA, (S)-3-hydroxydecanoyl-CoA, (S)-3-hydroxylauroyl-CoA?
I am not a chemist at all; I am looking at [the ChEBI ontology][1] and wondering why (S)-3-hydroxyoctanoyl-CoA, (S)-3-h... |
Just wondering.
http://periodictable.com/Elements/060/data.html conveys that Neodymium is paramagnetic. Yet the Neodymium magnets out there make extremely strong magnets. I'm guessing these are not pure neodymium magnets but some kind of compound.
Is it possible to predict the change in magnetic property of a co... |
How is the magnetic property of an element affected when the element is part of a compound? |
From [Wikipedia][1]
> Cosmeceuticals refers to the combination of cosmetics and
> pharmaceuticals. Cosmeceuticals are cosmetic products with
> **biologically active ingredients** purporting to have medical or
> drug-like benefits.
I was wondering what ingredients being "biologically active" means?
In cosmet... |
What does ingredients being "biologically active" mean? |
In my lecture notes for inorganic chemistry, it is stated that magnesium has high affinity for oxygen but is rather stable at room temperature in air.
Can anyone explain why this is the case?
|
Data on [this site](http://periodictable.com/Elements/060/data.html) conveys that Neodymium is paramagnetic. Yet the Neodymium magnets out there make extremely strong magnets. I'm guessing these are not pure neodymium magnets but some kind of compound.
Is it possible to predict the change in magnetic property of a c... |
There are lots of videos on YouTube showing sodium, potassium, etc. exploding when dropped into water ([this][1], for example).
I understand that when an alkali metal is exposed to water, a violent exothermic reaction occurs where a hydroxide and hydrogen gas are produced, but why and how does the sample of metal en... |
What exactly is happening when sodium, potassium, or other alkali metal explodes in water? |
There are lots of videos on YouTube showing sodium, potassium, etc. exploding when dropped into water ([this][1], for example).
I understand that when an alkali metal is exposed to water, a violent exothermic reaction occurs where a hydroxide and hydrogen gas are produced, but why and how does the sample of metal en... |
A typical organic light emitting diode (OLED) structure consisting of a glass substrate, a indium titanium oxide (ITO) anode, and an organic bilayer diffused into a metallic cathode, is given below:
![enter image description here][1]
The organic bilayer consists of:
- a **hole transport layer (HTL)**, typical... |
I'm working on some combustion problems using [Cantera][1] and I can't find references for the thermodynamic or transport properties for many of my chemical species. I'm looking for NASA-7 or NASA-9 curve-fits for the thermodynamics, although if there is another equation format that exists, I will make it work. And I ... |
I'm working on some combustion problems using [Cantera][1] and I can't find references for the thermodynamic or transport properties for many of my chemical species. I'm looking for NASA-7 or NASA-9 curve-fits for the thermodynamics, although if there is another equation format that exists, I will make it work. And I ... |
Can silica gel beads (which I believe are amorphous) when crushed to dust cause silicosis? |
can Silica gel beads (all types) cause silicosis if crushed? |
Can silica gel beads cause silicosis if crushed? |
I am looking for introduction to modeling of chemical reactions. I think there is the base approach, where concentrations of chemical species are given, plus ratios of each possible reaction / outcome. Is there a paper lightly explaining internal mechanics of such reactions, and their modeling via system of differentia... |
I prepared a isotonic solution of table salt in water following this recipe: 1 leveled coffee spoon of salt in 0,5l of water.
9g/l would be an isotonic solution, a leveld coffee spoon is commonly given as 5g - close enough. I use water from the tap, freshly boiled in a water cooker. The water is not chlorinated, I d... |
Why is my NaCl solution seemingly saturated, when I followd the recipe for an isotonic solution? |
I prepared an isotonic solution of table salt in water following this recipe: 1 leveled coffee spoon of salt in 0,5L of water.
9g/L would be an isotonic solution, a leveled coffee spoon is commonly given as 5g - close enough. I use water from the tap, which was freshly boiled in a water cooker. The water is not chlo... |
Why is my NaCl solution seemingly saturated, when I followed the recipe for an isotonic solution? |
Many uncharged organic compounds are sold in solid phase with HCl conjugate - e.g. the antihistamine [diphenhydramine.HCl][1] or the derivitizing agent [pentafluorobenzyl hydroxylamine.HCl][2], among many others. Assuming the compound will be dissolved at relatively low concentrations in a buffered medium (for instance... |
Why are solid phase organics often conjugated to HCl? |
I'm a gold smith and I want to start experimenting with non-standard metal-alloys. Now high school is a long time ago for me so while I think I've got this right, I'm just not as sure as I should be when working with precious metals costing 40 dollar a gram. So could anyone confirm that what I'm doing is right:
I ha... |
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