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tl;dr: You are likely to see more soot, $\ce{CO}$, $\ce{H2}$, less of $\ce{CO2}$ and same amount of $\ce{H2O}$.
There are different type of combustion that you can talk about. For example when you mix fuel and oxidizer before burning them, it is referred to as premixed system. For example a gas cooking range, gas tu... |
reaction of toluene? |
In IR, the vibrational frequencies of a simple diatomic molecule can be described by the following equation:
$$
\bar\nu = \frac{1}{2\pi c}\sqrt{\frac{k}{\mu}}
$$
Here, $k$ is the force constant, $\mu$ is the [reduced mass][1] of the molecule, and $c$ is the speed of light (which results in appropriate units for... |
The question may be off-topic here. If my concept is flawed, please poke me in the rib (+:
[Sources][1] on the internet indicate a minimum 1.2Volts is adequate for electrolysis of water; nominally 6V. Applying a DC source to water provides adequate energy to break the hydrogen bond. Apparently some heat is also rele... |
What is the heat energy required to perform electrolysis equivalent? |
Can we determine whether a reaction is endothermic or exothermic? For example if we are given the following reactions:
$$\ce{2SO2 + O2 -> 2SO3}$$
$$\ce{H2 + I2 ->2HI}$$
$$\ce{N2 + 3H2 -> 2NH3}$$
Can we determine weather these reactions are endothermic or exothermic or do we have to just memorize this? Are... |
I'm currently working on building a simulator for the early earth to examine the spontaneous occurrence of food generated autocatalytic sets. No one in my group is a chemist, so the bottle neck for the project is implementing some sort of realistic chemistry in our model.
We are considering using the software outlin... |
To model early earth chemical reactions which types of reactions should be included? |
I won't do any rib poking, but there is some flawed thinking here. Certainly not off topic though.
**Nomenclature:** First, when you pass a current through water, you are not breaking the hydrogen bonds, which are intermolecular forces, but (a) breaking the bond between hydrogen and oxygen and (b) forming molecular... |
I have read that paint contains VOCs(Volatile Organic Compounds), and solvents generally, and I could wait for them to dissipate, but i've read there are ways to remove the smell of paint such as half an onion in a bucket of water, such as slices of lemon on a plate, such as small bowls of distilled white vinegar.
D... |
does an onion completely remove "fresh" paint VOCs and other chemicals emitted? |
Does an onion completely remove "fresh" paint VOCs and other chemicals emitted? |
I'm looking for a material that I can use to make a mesh netting. It should be flexible and have reasonable tensile strength when cold but brittle when hot (400+ degrees F). I want to use it to contain charcoal when cold but disintegrate when charcoal is burning and some force is applied to it.
Any ideas? |
It is unlikely that a potential applied to a sodium electrode in water would prevent the spontaneous oxidation of sodium by water. Consider the following reduction potentials:
$$\ce{2Na+ + 2e- -> 2Na(s)}\ E^0=-2.71V\tag{1}$$
$$\ce{2 H2O + 2e- ->H2 + 2 OH-}\ E^0=-0.83V\tag{2}$$
The reduction of water will alway... |
This is an outdoors & chemistry question.
I have an old and functional water bladder, shown below. On it, there are markings that *coffee, beer, wine, hot drinks* etc. must NOT be stored inside, only water.
While I realize that wine is acidic, damaging the bladder and becoming poisonous, beer seems to me quite ... |
"Dringking water" plastic - can I store beer in this? |
Usually maximum time we see then after cooking by gas there is no black spot on the pot. But continually burning can affect the pot surface and makes black powder.
My question is:
> What is the most acceptable reason that black powder(carbon) take places on the pot surface. Is it related to the burning temperat... |
How does alum help 'clean' water? |
What does it mean to shift a chemical equilibrium? For example, the equilibrium shifts to the left... I don't understand that.. |
OK, so after a bit of researching this is what I've found. <hr>
**First of all,why does the dust not settle in the water in the first place?** Well, dust forms a kind of a suspension.
1. The particles are all similar and ionized, so therefore they have a similar charge (positive, I think) causing them repel each... |
To be precise, how does the addition of [alum][1] — to be specific, potassium aluminium sulfate or $KAl(SO_4)_2$ — help settle the dust particles in water?
There was such a statement in my Year 9 textbook, and so I was wondering how exactly alum does it.
I hope this is on-topic for the site and not a dupe (I coul... |
OK, so after a bit of researching this is what I've found. <hr>
**First of all,why does the dust not settle in the water in the first place?** Well, dust forms a kind of a suspension.
1. The particles are all similar and ionized, so therefore they have a similar charge (positive, I think) causing them repel each... |
The most common approach is to measure periodically.
pH glass electrodes (the most common ones) need to be "wet" in order to be used, so if you are going to remove it from the solution every hour you'll need to keep it submerged in the appropriate solution. Not only that, you need to wash it (preferably with the mos... |
The most common approach is to measure periodically.
pH glass electrodes (the most common ones) need to be "wet" in order to be used, so if you are going to remove it from the solution every hour you'll need to keep it submerged in the appropriate solution. Not only that, you need to wash it (preferably with the mos... |
How does the addition of [alum][1] — potassium aluminium sulfate or $KAl(SO_4)_2$ — help settle the dust particles in water?
There was such a statement in my Year 9 textbook, and so I was wondering how exactly alum does it.
[1]: http://en.wikipedia.org/wiki/Alum
[2]: http://chemistry.stackexchange.com/ |
What are the technical/scientific details behind the process of water deionization? How does deionization machines like those manufactured by [Millipore][1] work?
[1]: http://www.millipore.com/ |
How does water deionization process work? |
OK, so after a bit of researching this is what I've found. <hr>
**First of all,why does the dust not settle in the water in the first place?** Well, dust forms a kind of a suspension.
1. The particles are all similar and ionized, so therefore they have a similar charge (positive, I think) causing them repel each... |
I am attempting to optimize interactions for a series of random and test molecules to a protein using docking software. The software uses QM/MMGBSA to calculate free energy in joules (yes it is not a measurement but it is very corollary). Larger molecules automatically have more free energy because they have greater po... |
I am attempting to optimize interactions for a series of random and test molecules to a protein using docking software. The software uses QM/MMGBSA to calculate free energy in joules (yes it is not a measurement but it is very corollary). Larger molecules automatically have more free energy because they have greater po... |
I am attempting to optimize interactions for a series of random and test molecules to a protein using docking software. The software uses QM/MMGBSA to calculate free energy in joules (yes it is not a measurement but it is very corollary). Larger molecules automatically have more free energy because they have greater po... |
I am attempting to optimize interactions for a series of random and test molecules to a protein using docking software. The software uses QM/MMGBSA to calculate free energy in joules (yes it is not a measurement but it is very corollary). Larger molecules automatically have more free energy because they have greater po... |
How does the addition of [alum][1] — potassium aluminium sulfate or $KAl(SO_4)_2$ — help settle the dust particles in water?
There was such a statement in my Year 9 textbook, and so I was wondering how exactly alum does it.
**Edit:** I have posted an answer below based on what I've found, but I'd love it if some ... |
aromatic nucleophillic substitution? |
The key point to understanding why $\ce{F-}$ is such a good leaving group in the nucleophilic aromatic substitution (I will call it $\mathrm{S}_{\mathrm{N}}\mathrm{Ar}$ in the following) is knowing the rate determining step of the reaction mechanism.
The mechanism is the shown in the following picture (Nu = Nucleophil... |
In aromatic nucleophilic substitution why does $\ce{F-}$ acts as the best L.G.?
The reason I think is due to -I effect of fluorine being the greatest it leaves first.
((As it stabilizes messienmier complex))
But what about M effect and the criteria of L.G. order of $\ce{Br-}$ > $\ce{F-}$ |
The key point to understanding why $\ce{F-}$ is such a good leaving group in the nucleophilic aromatic substitution (I will call it $\mathrm{S}_{\mathrm{N}}\mathrm{Ar}$ in the following) is knowing the rate determining step of the reaction mechanism.
The mechanism is the shown in the following picture (Nu = Nucleophil... |
You're talking about the human body being exposed to outer space and asking about what would happen to it's internal structure. Bones, fats and proteins are within the enclosed system that is the human body, they are not subjected to the low pressures of space. The answer to `the pressure at which proteins, fats and bo... |
Find the difference in the maximum and mimimum oxidation state of S in $\ce{S4O6^{-2}}$.
My answer is 2 but the answer given is 5. Could you help? |
How chemists found how many electron, neutron, proton each element had?
I mean I can understand the Mendeleev's table but without really knowing how you make one... |
How did chemists find how many electrons, neutrons, and protons each element had?
I mean I can understand the Mendeleev's table but without really knowing how you make one... |
I have just recently learnt the theory of fractional and normal distillations and the basics of maximumand minimum boiling azeotropes. Most books say that the components of the mixture forming an azeotrope cannot be separated by distillation because on heating, the residue(in case of negative or maximum boiling azeotro... |
Azeotropes and separtation by distillation? |
I realise that tear gas can be several different things (Pepper spray / CS Gas / CR gas, PAVA, etc)
Is there a good way to detect some or any of these in the air?
Ideally using an electronic sensor that can be reused?
Thanks,
Tom
|
What is the best way to detect the presence of tear gas? |
I realise that tear gas can be several different things (Pepper spray / CS Gas / CR gas, PAVA, etc)
Is there a good way to detect some or any of these in the air?
Ideally using an electronic sensor that can be reused?
|
If we take a test-tube of bromine and invert an upside-down test tube of air on top of it, it'll diffuse with the air, until the bromine is thoroughly 'mixed' with the air in both test tubes. But why doesn't the same thing happen with two immiscible liquids? Say oil and water.
When you put a layer of oil on top of wa... |
Why doesn't diffusion take place between immiscible liquids? |
How does the addition of [alum][1] — potassium aluminium sulfate or $\ce{KAl(SO4)2}$ — help settle the dust particles in water?
There was such a statement in my Year 9 textbook, and so I was wondering how exactly alum does it.
**Edit:** I have posted an answer below based on what I've found, but I'd love it if so... |
Its there in every high-school textbook: $O_2$ is the supporter of combustion. Without $O_2$ combustion cannot take place. Why? And why only $O_2$? Why not some other element?
And, what happens when a combustible gas burns in air? Say $H_2$? |
Why is $O_2$ the supporter of combustion? |
The reaction of sodium with water is quite infamous.
$2Na + 2H_2O \rightarrow 2NaOH + H_2$
But exactly why does $Na$ displace $H$ in $H_2O$? |
Why does sodium react with water? |
The reaction of sodium with water is quite infamous.
$\ce{2Na + 2H_2O \rightarrow 2NaOH + H_2}$
But exactly why does $\ce{Na}$ displace $\ce H$ in $\ce{H_2O}$? |
I'm going to study the thermal expansion of graphite. For this goal, I should change the temperature continuously. But I do not know how to code it by [Lammps][1]?
[1]: http://lammps.sandia.gov |
(Any experienced user of Lammps, here?) How to write an input Lammps command for continuous change in temperature? |
I have just recently learnt the theory of fractional and normal distillations and the basics of maximum and minimum boiling azeotropes. Most books say that the components of the mixture forming an azeotrope cannot be separated by distillation because on heating, the residue(in case of negative or maximum boiling azeotr... |
How would I write an input Lammps command for continuous change in temperature? |
How do you determine concentration of a sample using wavelength and absorbency? Say our wavelength for a sample of Red 40 is 508.50 nm and absorbance is 0.283 when we use 6ml water and 4 ml Red 40. What would be our concentration? This is really frustrating me so any help would be appreciated. |
How do you determine concentration of a sample using wavelength and absorbency? Say our wavelength for a sample of Red 40 is 508.50 nm and absorbance is 0.283 when we use 6ml water and 4 ml Red 40. What would be our concentration and the slope ε? This is really frustrating me so any help would be appreciated. |
How can you accurately qualitatively and quantitatively determine the HCN in a volatile product from water ? |
How to estimate HCN content in a volatile mixture? |
I don't know anything about Red 40, but you will need the extinction coefficient. Perhaps you determined this from a plot of concentration *vs* absorbance in the lab?
I am going to attempt to answer you question with reference to [NADH](http://en.wikipedia.org/wiki/Nicotinamide_adenine_dinucleotide), which has an... |
I don't know anything about Red 40, but you will need the extinction coefficient. Perhaps you determined this from a plot of concentration *vs* absorbance in the lab?
I am going to attempt to answer you question with reference to [NADH](http://en.wikipedia.org/wiki/Nicotinamide_adenine_dinucleotide), which has an... |
I don't know anything about Red 40, but you will need the extinction coefficient. Perhaps you determined this from a plot of concentration *vs* absorbance in the lab?
I am going to attempt to answer you question with reference to [NADH](http://en.wikipedia.org/wiki/Nicotinamide_adenine_dinucleotide), which has an... |
I don't know anything about Red 40, but you will need the extinction coefficient. Perhaps you determined this from a plot of concentration *vs* absorbance in the lab?
I am going to attempt to answer you question with reference to [NADH](http://en.wikipedia.org/wiki/Nicotinamide_adenine_dinucleotide), which has an... |
I don't know anything about Red 40, but you will need the extinction coefficient. Perhaps you determined this from a plot of concentration *vs* absorbance in the lab?
I am going to attempt to answer you question with reference to [NADH](http://en.wikipedia.org/wiki/Nicotinamide_adenine_dinucleotide), which has an... |
The most likely cause of a "soapy" taste and sudsing from filtered water is a reverse osmosis filter, for which the usual [membrane preservative][1] used to keep the filter from degrading before its first use is plain old glycerin, a common ingredient in and byproduct of traditional soap (though most cleansing products... |
I'm not sure whether the caffeine contained in otc caffeine pills is made synthetically or isolated from coffee and other plants, but if the latter is the case, is it likely that it contains the chemical harmane? I ask because I suffer from essential tremor and it has been speculated that one component of ET is an inab... |
I'm attempting to write a small program that will calculate the values for the Ideal Gas Law, specifically for molecular Hydrogen (H2) in space. Eventually, this will grow to be a sort of "simulator", but right now I seem to be having problems with remembering my college chemistry and physics.
Here is a picture of ... |
First, how certain are you that the most common sources of caffeine (i.e., coffee beans, tea leaves, etc.) actually contain harmala alkaloids at all? In the research I did for this question, I didn't see them mentioned. However, I'll assume your sources are good and they're present in some quantity for the purposes of ... |
First, how certain are you that the most common sources of caffeine (i.e., coffee beans, tea leaves, etc.) actually contain harmala alkaloids at all? In the research I did for this question, I didn't see them mentioned. However, I'll assume your sources are good and they're present in some quantity for the purposes of ... |
Given that caffeine can be readily extracted from a variety of abundant and exceedingly cheap natural sources, I doubt it would be economical to synthesize. Various decaffeinated products are popular, and the caffeine removed during the decaffeination process is normally recovered, purified, and re-sold for use in vari... |
So say I have a reaction where there are x moles of gas on the reactant side, and y moles of gas on the product side, where x>y. The volume decreases, favoring the products side. The textbook I am using says that the equilibrium concentration of the reactants would decrease, but wouldn't it end up increasing due to the... |
Would concentration of a compound in equilibrium increase even if it's not favored by a volume decrease? |
I'm not sure whether the caffeine contained in otc caffeine pills is made synthetically or isolated from coffee and other plants, but if the latter is the case, is it likely that it contains the chemical harmane?
It's claimed that isolated caffeine is 99% pure and I'm wondering whether the remaining 1% is likely ... |
Does caffeine isolated from coffee contain harmane? |
This is my first post on chemistry stack exchange :)
I am running experiments using reagents preserved with 0.1% sodium azide, which are applied to a gold film. Unfortunately, there are very few options for using reagents without sodium azide.
I understand that sodium azide reacts with gold to form heavy metal a... |
It may sound off-topic, but I am interested to know the following:
1. Which gems can be prepared at home(without sophisticated instruments) ?
2. What will be the quality(appearance) of the product for a certain method ?
I want these information just for hobby purposes(no academic/commercial importance). |
Which gems can be prepared on a small scale basis ? |
Most likely the only gems you will be able to make at home are [plastic gems][1].
Wikipedia sheds some light on the production of some synthetic gems, [Corundum][2] and [Cubic Zirconia][3], both of them not possible at home (or at least my home).
[1]: http://www.youtube.com/watch?v=u-BEya1xsjA
[2]: htt... |
I am interested to know the following:
1. Which gems can be prepared at home(without sophisticated instruments) ?
2. What will be the quality(appearance) of the product for a certain method ?
I want these information just for hobby-scale purposes(no academic/commercial production). |
Which gems can be prepared on a small scale basis? |
I use a silver based disinfectant in my hot tub. It is in the form of silver nitrate beads. There is chlorine in the tub that I presume becomes chloride ion. Why doesn't the silver form a precipitate of silver chloride in the water? |
I am running experiments using reagents preserved with 0.1% sodium azide, which are applied to a gold film. Unfortunately, there are very few options for using reagents without sodium azide.
I understand that sodium azide reacts with gold to form heavy metal azides, which are explosive.
I would like to know:... |
My friend recently bought a ruby gem from a store and asked me how to test whether its an original one or a duplicate.
Are there any ways to test it using only domestic materials? |
what is the procedure to test ruby gems? |
I just bought a butter dish which is a millimeter or two too small (the problems are that the corners are rounded which they forgot to mention before I ordered it and asked for the dimensions) to fit a piece of butter as it is sold in the supermarket. Since I don't want to return it my idea was to freeze the butter bef... |
How much does butter shrink when frozen? |
I am interested to know the following:
1. Which gems can be prepared at home(without sophisticated instruments) ?
2. What will be the quality(appearance) of the product for a certain method ?
I want these information just for hobby-scale purposes(no academic/commercial production).
**UPDATE**
In additi... |
Given that fat (consisting mainly of assorted triglycerides of varying saturation) is the major constituent by a wide margin, it's probably reasonable to compare the change in density w/r/t temperature of butter to the change measured in various vegetable oils, since they have roughly comparable chemical composition (a... |
Given that fat (consisting mainly of assorted triglycerides of varying saturation) is the major constituent by a wide margin, it's probably reasonable to compare the change in density w/r/t temperature of butter to the change measured in various vegetable oils, since they have roughly comparable chemical composition (a... |
Given that fat (consisting mainly of assorted triglycerides of varying saturation) is the major constituent by a wide margin, it's probably reasonable to compare the change in density w/r/t temperature of butter to the change measured in various vegetable oils, since they have roughly comparable chemical composition (a... |
I really don't understand why metals form metallic bonds. I mean, it makes no sense. It would make much more sense for them to form covalent bonds with themselves and have a 'pseudo-full' outer shell. How does freeing off electrons make them any more stable? |
Why don't metals form covalent bonds? |
How can one test if a ruby is real? |
A friend of mine was looking over the definition of pH, and wondering if it is possible to have a negative pH level. From the equation below, it certainly seems possible--just have a $1.1$ (or something $\gt 1$) molar solution of $H^+$ ions:
$$\text{pH} = -\log([H^+])$$
(Where $[X]$ denotes the concentration of $X$ ... |
Is a negative pH level physically possible? |
Also, can you explain why, as in which solubility rules apply in this case? |
Is Mn(C2H3O2)2 soluble in water? |
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