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In other [site][1], someone claimed that pure water is very corrosive.
>Water distilled for some laboratory uses (like the Z-pinch reactor) is distilled to 0.00000009% purity, and is caustic enough to burn through most things.
>Water, purified enough, cannot be distributed through stainless steel pipes. Instead, ... |
Is pure water very corrosive? |
On what basis can the SRP value of different elements in the periodic table be explained?
For example why does Cu have a greater tendency to accept an electron and Zn have a tendency to lose electrons in a Daniel cell? |
What is chemical free energy?How can we practically explain its existance?How can it be used to do some useful work like in an electrochemical cell?
I couldn't understand clearly about it when I referred a few books |
What is chemical free energy? |
What is chemical free energy? How can we practically explain its existence? How can it be used to do some useful work like in an electrochemical cell?
I couldn't understand clearly about it when I referred a few books |
**Chemical Free Energy or Gibbs Free Energy is best understood as potential energy for reactions.**
If I have a lot of Gibbs Free Energy, then I have a lot of potential energy.
Kind of like if I were on top of a hill, it's very easy for me to roll down that hill.
Often what's talked about in books is dG or the c... |
Several of my friends, when they do the dishes manually, do not rinse the dishes after cleaning but merely dip them in the dishwater and then dry them (using a towel or a dish rack). I myself on the other hand always rinse the dishes with fresh (hot) water from the tap before drying them, mostly because the idea of hav... |
Is dishwashter containing soap unhealthy? |
How do you determine the migratory "aptitude" of various groups during carbocation rearrangements? Is there a experimentally determined order?
For example, what will be the product in case of the following [pinacol-pinacolone type rearrangement][1]:-
$$\ce{(cyclo-pentyl)CH3C(OH)-C(OH)(CH3)(cyclo-pentyl) ->produc... |
Determination of products in reactions involving carbocation rearrangement? |
I am finding a good way to liquefy or extract water from superabsorbent polymer. From what I remember it was salt that can liquefy it. Since salt when dissolve will have sodium cation and there for naturalize the polymer chain making it contract. Is that true?. Thank very much. |
![1][https://dl.dropboxusercontent.com/u/58123953/Naming%20Alkanes%20Confusion.PNG
I'm wondering why the above image is named 5-ethyl-3,3-dimethylheptane rather than 3-ethyl-5,5-dimethylheptane. I thought ethyls have a higher priority (I know this is true when arranging the final name, but what about numbering the p... |
I'm wondering why the above image is named 5-ethyl-3,3-dimethylheptane rather than 3-ethyl-5,5-dimethylheptane. I thought ethyls have a higher priority (I know this is true when arranging the final name, but what abo... |
I know the [mechanism of aldol condensation][1] and general method to determine products in [crossed aldol reactions][2], or reactions between dissimilar molecules. But the following statement in my class notes baffles me:-
> In presence of a base (alkaline mediu) the $\alpha$ hydrogen of the
> lower aldehyde... |
I'm wondering why the above image is named 5-ethyl-3,3-dimethylheptane rather than 3-ethyl-5,5-dimethylheptane. I thought ethyl substituent has a higher priority (I know this is true when arranging the final name, bu... |
I'm wondering why the above image is named 5-ethyl-3,3-dimethylheptane rather than 3-ethyl-5,5-dimethylheptane. I thought an ethyl substituent has a higher priority (I know this is true when arranging the final name,... |
In the fantastic TV series Breaking Bad, Walter White, the dying chemistry teacher, takes to making crystal meth (d-methamphetamine) by several routes.
Initially, he uses the common small-scale route starting with pseudo-ephedrine which uses a stereospecific starring material to make a stereospecific end product (d-... |
How does Walter White make pure crystal meth using a non-stereospecific reaction? |
I'm clear with the concepts of crystal field theory. But I can't point out the exact reason why is the hybridisation of potassium permanganate ($\ce{KMnO4}$) is $d^3s$. Can anyone explain please? |
Yes there is a scientific basic but I think you can't do anything with the apparatus shown in figure. [Here](http://weakinteractions.wordpress.com/2010/05/01/the-science-of-breaking-bad-sunset/) you can find many information about it. I will try to summarize.
It seems that extracting coffee at lower temperature ma... |
Yes there is a scientific basic but I think you can't do anything with the apparatus shown in figure. [Here](http://weakinteractions.wordpress.com/2010/05/01/the-science-of-breaking-bad-sunset/) you can find many information about it. I will try to summarize.
It seems that extracting coffee at lower temperature ma... |
Does Cysteine break down in filtered water? Should this be made more acidic?
If I mix Cysteine powder in juice (something acidic maybe), does it remain at Cysteine? It seems that it can oxidize into Cysteine and lose some of its qualities. |
How to compute the electron configuration of an (electrically neutral) atom ?
So when given the atom number how does noe compute the electron configuration ?
I know the sum of electrons must equal the atom number.
I also know the first shells fill up as 2n^2.
I do not know how to compute quantum numbers whe... |
How to compute the electron configuration of an atom? |
I'm studying civil engineer in my first year. We have a course called "General Chemistry". One of the chapters was about chemical balance of a reaction (called equilibrium in English, I think). We got exercises on this were we had to calculate the amount of chemicals got converted to others, using acidity constants Ka.... |
I'm studying civil engineer in my first year. We have a course called "General Chemistry". One of the chapters was about chemical balance of a reaction (called equilibrium in English, I think). We got exercises on this were we had to calculate the amount of chemicals got converted to others, using acidity constants Ka.... |
I'm studying civil engineer in my first year. We have a course called "General Chemistry". One of the chapters was about chemical balance of a reaction (called equilibrium in English, I think). We got exercises on this were we had to calculate the amount of chemicals got converted to others, using acidity constants Ka.... |
Complex roots to mass/concentration balance equations should be discarded as they have no physical interpretation. If there are only complex roots, then odds are there's some error in the manipulation of variables that lead to the equation.
Your case seems different though. Notice the very small magnitude of the im... |
Complex roots to mass/concentration balance equations should be discarded as they have no physical interpretation. If there are only complex roots, then odds are there's some error in the manipulation of variables that lead to the equation.
Your case seems different though. Notice the very small magnitude of the im... |
To calculate electronic configurarion you need to know several thing first.
**[Electron Shell][2]**
>In chemistry and atomic physics, an electron shell, also called a principal energy level may be thought of as an orbit followed by electrons around an atom's nucleus. The closest shell to the nucleus is called t... |
To calculate electronic configurarion you need to know several thing first.
**[Electron Shell][2]**
>In chemistry and atomic physics, an electron shell, also called a principal energy level may be thought of as an orbit followed by electrons around an atom's nucleus. The closest shell to the nucleus is called t... |
How to compute the electron configuration of an (electrically neutral) atom ?
So when given the atom number how does one compute the electron configuration ?
I know the sum of electrons must equal the atomic number.
I also know the first shells fill up as $2n^2$.
I do not know how to compute quantum numbers... |
There are several resources available for this, for example, searching in [Google Scholar][1] yields over 37,000 articles (this is without any filters for age or specifics).
Organisations such as the American Chemical Society have a searchable [publications link][2]; related, CAS has a [searchable reference list][3]... |
I understand we can calculate the maximum work done by the electromotive force (driving electrons through a cell) by multiplying the potential of the cell with the charge of one mole of electrons (faraday s constant) and with "the number of moles of electrons involved in the reaction". I thought that in the case of a h... |
I understand we can calculate the maximum work done by the electromotive force (driving electrons through a cell) by multiplying the potential of the cell with the charge of one mole of electrons (faraday's constant) and with "the number of moles of electrons involved in the reaction". I thought that in the case of a h... |
I understand we can calculate the maximum work done by the electromotive force (driving electrons through a cell) by multiplying the potential of the cell with the charge of one mole of electrons (Faraday's constant) and with "the number of moles of electrons involved in the reaction". I thought that in the case of a h... |
My book says that electrophilic bromination of toluene (methylbenzene) is faster than that of ethylbenzene. How is that possible?
I am doubting it because ethyl is a better $+I$ group than methyl, so ethyl would increase the electron density in the benzene ring more than methyl. As a result, bromine, which is an ele... |
Is it an ion or a neutral atom that is created through Beta decay?
For example: $_6^{14}C → _7^{14}N + e^- + {v{_e}}^{-}$
Isn't $_7^{14}N$ an ion since neutron gives us only a proton and an electron, not a proton and 2 electrons? If so, why isn't it stated in the example above (it's from Wikipedia)?
Thanks f... |
Is it an ion or a neutral atom that is created through Beta decay?
For example: $_6^{14}\mathrm C \to ~ _7^{14}\mathrm N + \mathrm e^- + \mathrm{v{_e}}^{-}$
Isn't $_7^{14}N$ an ion since neutron gives us only a proton and an electron, not a proton and 2 electrons? If so, why isn't it stated in the example above... |
Having mixed powder of KCl, NaCl and MgCl2 (and, perhaps, some crap) how to separate the components? |
How to separate KCl from NaCl and MgCl2? |
Can bromide ion reduce ferric ion ?
Just a query?
In my opinion it can since Br has oxidation state -1 and it can undergo oxidation.
Is my answer correct? |
Can bromide ion reduce ferric ion? |
Can bromide ion reduce ferric ion ?
Just a query.
In my opinion it can since bromide ion can undergo oxidation.
Is my answer correct? |
Further to @ManishEarth's answer, note that the distinction is important in doing mass-energy calculations. In the above example, you can find the energy released by subtracting the ***tabulated*** mass of a $N^{14}$ atom from the ***tabulated*** mass of the $C^{14}$ atom, and ignore the electron mass. Why? Because ... |
Sulphur belongs to the same group as Oxygen. Then why Oxygen exists as an $O_2$ molecule while Sulphur exists as $S_8$ molecule? What's the Chemistry behind it? |
Why does sulphur exist as $S_8$ molecule? |
I do know that the lanthanides start with the element lanthanum, but why? Lanthanum doesn't even have an $f$ orbital, so why isn't it considered a transition metal?
It's the same way with actinium, which doesn't even have any electrons in its $5f$ orbital, why isn't it also a transition metal? |
Why is lanthanum a lanthanide and actinium an actinide? |
I was recently asked the question "Why are noble gases stable? with the expectation of providing an answer beyond the general explanation of "they have full valence layers" and I couldn't think of one.
I would love to hear a full description of the this stability, I have a solid background in quantum mechanics, so ... |
How come when a non polar molecule increases in size, the attractive forces between the molecules of a substance also increase?
I thought that when a molecule increases in size, the atomic radius increases, which creates a bigger space between particles; thus, the force of attraction would be weaker.
But, why do... |
Evaporating the water of a solution of only $CO_3^{2-}$ ions and water gives? |
Evaporating the water of a solution of only carbonate ions and water gives? |
Having mixed powder of $KCl$, $NaCl$ and $MgCl_2$ (and, perhaps, some crap), how can the components be separated? |
How to separate $KCl$ from $NaCl$ and $MgCl_2$? |
How to separate KCl from NaCl and MgCl2? |
Having mixed powder of $\ce{KCl}$, $\ce{NaCl}$, and $\ce{MgCl2}$ (and, perhaps, some crap), how can the components be separated? |
Why do we only consider pka vlue of any drug however it is acid or base? Why do we not prefer pkb value?
|
As I mentioned in the comments, a quantitative separation of the three compounds will probably not be possible outside of a proper laboratory, however a coarse separation is possible. A quick search on the internet yields [this link][1] for the separation of $\ce{NaCl}$ and $\ce{KCl}$. You didn't give us the exact comp... |
As I mentioned in the comments, a quantitative separation of the three compounds will probably not be possible outside of a proper laboratory, however a coarse separation is possible. A quick search on the internet yields [this link][1] for the separation of $\ce{NaCl}$ and $\ce{KCl}$. You didn't give us the exact comp... |
When I name an organic compound, I follow a preferential order like so: http://www.masterorganicchemistry.com/2011/02/14/table-of-functional-group-priorities-for-nomenclature/ But I don't understand why this order exists. And intuitively (to me at least), a triple bond has a higher preference than a double bond... then... |
Why do we only consider the pka vlue of a drug regardless of whether it is an acid or base? Why do we not use the pkb value?
|
This data was taken for my science fair project, and I would like to know the relationship between spectrophotometer absorbance and cell density (taken manually) of algae after a toxicity test. The different levels of toxicity are IC 0 (no chemical), IC 25, IC 50, IC 100 (the most chemical). The IC value is basically... |
Does my data show quadratic regression in a calibration curve? |
It doesn't seem as though the hybridization model adds anything useful to the discussion of molecular geometry as predicted by the VSEPR model. It's just another way of labeling linear, trigonal planar, and tetrahedral geometry (as $sp$, $sp^2$, and $sp^3$, respectively). Considering that orbital hybridization may not ... |
Does the hybridization model gives us any further insight on Molecular Geometry? |
Following is the question that was asked in my exam. a,b,c,d are the various options, one of which is the answer. I am familiar with the [Reformatsky reaction][1], Aldol condensation, [Knoevenagel's reaction][2] and general base catalysed carbonyl reaction. 1 and 2 are my attempts at deriving the mechanism and hence ge... |
I find orbital hybridization of very limited use. Orbital hybridization is a mathematical manipulation of atomic wavefunctions, but that that is the only relationship to a quantum mechanical description of an atom. Presently, we have no evidence that supports the claim that orbital hybridization happens. The reason ... |
As you have correctly assumed, the relationship between absorbance and absorbant concentration is linear (law of [Lambert-Beer][1]):
$$ A = \varepsilon \, l \times c$$
This should give you a straight line through (0,0) and your data.
Now, for a graphical analysis of data, let's not look at the numbers themselves... |
This may be a silly question but why is water wet?
All the previous questions on water do not explain the reason why is water wet. They assume that its a natural property. However we need to understand why is it wet in the first place. This could apply to other liquids such as milk, juices but the essential element i... |
Why is water wet and fire hot? |
I have right now read the concept of brownstead and lowry and also arhennious to define a substance that it is acid or base. Our teacher told us that there are substances which behave both like acid and a base. He proved this to us using example of water and Ammonia, he also asked us to find other substances like that?... |
There are some interesting laboratory reactions that use liquid ammonia as a solvent (for example, the [Birch Reduction][1] where an alkali metal is dissolved in liquid ammonia).
There have also been some high volume industrial processes that use liquid ammonia as a solvent (the weedkiller paraquat has two, quite di... |
Are there any significant industrial processes that use liquid ammonia as a solvent? |
I have read about the Brønsted-Lowry and Arrhenius concepts to define a substance as an acid or a base. Our teacher told us that there are substances which behave both as an acid and a base, using water and ammonia as examples. He also asked us to find other substances with the same behavior. Does anyone know any more ... |
Are there any amphoteric substances other than H2O and NH3? |
EDTA (Ethylenediaminetetraacetic acid) has a structure like this
![enter image description here][1]
[1]: https://i.stack.imgur.com/LSKnz.png
But as the name 'Ethylene' suggests why it doesn't have a double bond between carbons? |
Why EDTA doesn't has a double bond? |
Klaus Warzecha has already provided the correct mechanism, but I'd like to offer a supplementary discussion.
One approach here would be to attempt to eliminate some of the options based simply on first principles. Choices **(b)** and **(c)** seem improbable _prima facie_ for reasons of thermodynamics: the carbonyl m... |
EDTA (Ethylenediaminetetraacetic acid) has a structure like this
![enter image description here][1]
[1]: https://i.stack.imgur.com/LSKnz.png
But why, as the name 'Ethylene' suggests, doesn't it have a double bond between carbons? |
Why doesn't EDTA have a double bond? |
EDTA (Ethylenediaminetetraacetic acid) has a structure like this
![enter image description here][1]
[1]: https://i.stack.imgur.com/LSKnz.png
But why, as the name 'Ethylene' suggests, doesn't it should have a double bond between carbons? |
If atoms are mostly empty space then how are we able to interact with things? |
Our city sprays brine on the roads in the winter to prevent people from sliding around. It works but it makes it impossible to keep vehicles clean. One thing I've noticed is that the brine sticks to the city buses outlining the frame underneath the body panels, like so:
![enter image description here][1]
Doing so... |
Why does road salt reveal this bus's frame? |
So I have several descriptions of reactions and I have to give the net ionic equation. Are these just the equations or are they the proper net ionic ones?
Solid calcium is added to warm water.
$$\ce{Ca_{(s)} + 2 H_{2}O_{(l)} -> Ca^{2+}_{(aq)} + 2 OH_{(aq)}^- + H2_{(g)}}$$
Powdered magnesium oxide is added to a ... |
I am trying to figure out the shape of the Iodate Ion or IO3^-. No matter how many times I draw it, I keep getting Iodine in the centre, and 3 Oxygen atoms surrounding it, 2 with single bonds, and 1 with a double bond. This would make it a trigonal planar shape. It would mean that it is not a "bent" shape.
I went to... |
Iodate Ion (IO3-). Is it polar or non-polar? |
I might be terribly wrong, but I'm not aware of any other industrial process involving ammonia as a reactant (fertilizers, caprolactam, amino acids) where liquid ammonia is used as a solvent.
As a side note, liquefication at least plays a role over here (Germany) for the transport in [rail tank cars][1].
[1... |
Does Cysteine break down in filtered water? Should this made more acidic?
If I mix Cysteine powder in juice (something acidic maybe), does it remain at Cysteine? It seems that it can oxidize into Cystine and loose some of its qualities. |
Is it realistic to have a natural oxygen source in a cave? I am writing a story, about people who live underground in a land that is freezing outside. Heat is taken care of by geothermally heated groundwater. How do I make it realistic for these people to breath in the caves? |
Is it realistic to have a natural oxygen source in a cave? |
Suppose that I have 10 kg of plastic/polymer that is non solvable in water. I then divide the plastic/polymer into two equal parts. In other words, each part is 5kg. Let us name the parts A and B in order to identify them. I then proceed to make beads from each part. I make $n_A$ beads of radius $r_A$ from part A. I a... |
I want to make some homemade ink suitable for amateurs to practice calligraphy. I have access to many household chemicals, including acetic acid, sodium hydrogen carbonate, sugar, sodium chloride, and more.
Can someone give me an easy recipe for a colored (any color will be fine) ink that I can make at home? (prefer... |
Imagine some $S_N2$ reaction involving an aliphatic $sp^3$ carbon with a halide leaving group (e.g. Iodide or Bromide). Given the rise of femtosecond spectroscopy (e.g. using a mode-locked Ti:sapphire laser) and even attosecond spectroscopy, I'm curious if there are any studies that have measured the properties and ap... |
Suppose that I have 10 kg of plastic/polymer that is non solvable in water. I then divide the plastic/polymer into two equal parts. Let us name the parts A and B in order to identify them. I then proceed to make beads from each part. I make $n_A$ beads of radius $r_A$ from part A. I also make $n_B$ beads of radius $r... |
According to [this page][1], the CO2 buildup in the cave might also be a problem.
But, if there was a river that ran on the surface, then oxygen and nitrogen would dissolve into the water. The stream could then pass into the cave and release some of the dissolved oxygen into the oxygen deficient environment in the ... |
We know that pure water does not conduct electricity, but salt water is a decent conductor. This is commonly explained by saying that "the ions carry the current through the solution", an explanation that doesn't really make sense because it is not clear what will happen when all of the ions have migrated to the electr... |
Can an aqueous solution conduct electricity forever? |
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