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Calcium hypochlorite is supposed to be added to water. If a little water is added to the hypochlorite, it can start to oxidize and produce stronger chloric acid. The SDS says to avoid water and moisture. To test this, try adding just a few drops of water to a pile of powder or a pill and see if a reaction begins.
U... |
$1.$After adding two or more numbers, the number of digits after the decimal in the result=Least no. of digits after the decimal in the numbers being added.
$2.$After multilplying two numbers, no. of significant figures in a result= no. of significant figures in a number with least no. of significant figures, out of... |
We had a malfunction with the chlorination system at our pool. There was a reaction between the Calcium Hypochlorite tablets and either $\ce{CO2}$, Carbonic Acid, or Muratic Acid. There was a definite malfunction that led undetermined amounts of $\ce{CO2}$ (or a mixture of that gas dissolved into water, carbonic acid... |
>Why these two rules are made?
These rules are approximations of more sophisticated error propagation treatment. For addition and subtraction, for example, if the first number is a ± 0.1 and the second is b ± 0.001, and the numbers are independent of each other and normally distributed, the absolute error of the sum... |
In the chloride process (the process used to create titanium oxide from titanium ore), how is TiO2 collected? What prevents the TiO2 from building up on the walls of the reactor chamber? |
> Why thermodynamical equations are just for gases?
They are not. The equation $\Delta U = q + P\Delta V$ applies to any phase (gas, liquid, solid...) when *only* pV work is done. In the particular form of the equation you present, the pressure is in addition constant during the work.
Gases are (1) an easy way ... |
Thermodynamics has always been a tough thing for me. There are lots of assumptions in this subject (those assumptions, I know, are necessary, I know the science of thermodynamics is a very practical science).
First Law of Thermodynamics states mathematically:
$$\Delta U=Q+W$$
(with proper sign conventions must be ... |
Consider two metal blocks, one at 500K and another at 300K, they are bought to contact with each other until they reach a common temperature.
Find the entropy change of each object and the total change considering there is no change in the volume of the metal blocks in the process and no the other interactions excludi... |
> A neutral atom is an atom with an equal number of protons and electrons [...] The "neutral" in a neutral atom means electrically neutral.
Neutral in this case means net neutral. It does not mean that the opposite charges "destroy" each other. After all, the electrons are still attracted to the nucleus even though ... |
My understanding is that a stronger bond has a higher wavenumber in IR spectrum. But why C-H vibration has higher wavenumber than C=O vibration? The latter is double bond so I think it should be a stronger bond than C-H single bond. |
My understanding is that a stronger bond has a higher wavenumber in IR spectrum. But why does the C–H vibration have a higher wavenumber than the C=O vibration? The latter is a double bond, so I think it should be a stronger bond than the C–H single bond. |
Why does the weaker C–H bond have a higher wavenumber than the C=O bond? |
In general chemistry texts, the electron configurations are sometimes shown in boxes with up and down arrows to show the concept of paired spins. My impression for years was that Hund used such diagrams. However, flipping through his book *Linienspektren und Periodisches System der Elemente* which used the s,p, d, f no... |
In the chloride process (the process used to create titanium oxide from titanium ore), how is TiO2 collected? What prevents the TiO2 from building up on the walls of the reactor chamber?
EDIT: I have reworded the question here with some background: It's my assumption that the solid titania produced in a TiCl4+O2 rea... |
In the chloride process (the process used to create titanium oxide from titanium ore), how is TiO2 collected? What prevents the TiO2 from building up on the walls of the reactor chamber?
It's my assumption that the solid titania produced in a TiCl4+O2 reaction (assuming that the TiCl4 and O2 are all gases at 200 C) ... |
I looked at the flames of copper (I) chloride and of copper (II) chloride through a spectroscope and they looked the same. The flame colour is the same too. But since they have different oxidation states, and therefore different electron configurations, should their emission spectra be slightly different?
Would this... |
Do different oxidation states of the same element have the same emission spectrum? |
It is a very general question. Is there a good way to systematically increase the accuracy and precision of a measuring tool using only mathematical means? For example, average 10 measurements can create a better one. Or using two independent tools. I don't know if measuring theory or statistical quality control or o... |
Your non-trivial question has a yes and a no. It is not possible to increase the accuracy of a dataset just by mathematical means. If you knew the systematic error in your data then you can do the arithmetic to correct the error. There is no *a priori* way to ascertain if your measurement tool lacks accuracy until and ... |
We had a malfunction with the chlorination system at our pool. There was a reaction between the Calcium Hypochlorite tablets and either $\ce{CO2}$, Carbonic Acid, or Muriatic Acid. There was a definite malfunction that led undetermined amounts of $\ce{CO2}$ (or a mixture of that gas dissolved into water, carbonic aci... |
Was it CO2 or Muriatic Acid? |
The following graph denotes the variation of the compressibility factor (Z) with pressure at different temperatures for a real gas. Simply each of the curves represents an isotherm.
[![enter image description here][1]][1]
Now, suppose we are not given the temperatures and we are asked to find the temperature rela... |
How to find the temperature relationship between the isotherms in a compressibility factor (Z) vs pressure graph? |
I have 25L drums of Copper Tetrafluoroborate waste solution.
Can it be neutralised, precipitated in some way, to minimise the amount of waste that goes to landfill?
also, landfills prefer solid waste instead of liquid, so is there any cost effective way to reduce Copper Tetrafluoroborate to a solid?
|
The hydrogen atoms in a water molecule are negatively charged, so they should repulse each other completely due to the electromagnetic force, forcing the hydrogen atoms to be on opposite sides of the oxygen atom. However, this is not the case, as the H-O-H bond angle is $104.5 ^\circ$.
Why does the lone electron pai... |
Your non-trivial question has a yes and a no. It is not possible to increase the accuracy of a dataset just by mathematical means. If you knew the systematic error in your data then you can do the arithmetic to correct the error. There is no *a priori* way to ascertain if your measurement tool lacks accuracy until and ... |
Are Van der Waals coefficients independent of temperature? |
Are van der Waals coefficients independent of temperature? |
I am attempting to recycle or find a use for chlorodifluoromethane, however I do not want to risk venting it into the atmosphere or exposing myself to hydrofluoric acid. Ideally, I would like to produce chlorine/fluorine salts for safe storage/disposal.
Edit: Upon further research, calcium fluoride appears to be a ... |
Will Chlorodifluoromethane (R22 refrigerant) react with calcium metal? |
I was recently reading about the transition metals and some important compounds of them. I came across a rather *interesting* diagram in my book... a *tetrahedral* structure for the chromate ion. The *only* tetrahedral structure I know arises from an sp3 hybridization of the central atom, but as far as *chromium* is co... |
What is the hybridization of chromium in chromate and dichromate ions? |
The specific example I saw recently was cleansing of concrete (portland cement) film from brick using a diluted muriatic acid. It appeared that the more scrubbing was used, the quicker the cleaning process would go. That seems to match up with everyday experience.
However what is not clear is how that mechanical agi... |
Can mechanical agitation increase the reaction rate? |
What is the mechanism of oxidation of phenol to benzoquinone? |
Rather than design something that offers danger of overheating, carbon monoxide poisoning, gas and over-pressure explosion, etc., why not use an off-the-shelf "instant" tankless water heater, available from sources such as [Home Depot][1], [Amazon][2] or [Lowes][3]?
Find one certified for your area. Making your own ... |
To add to @Poutnik's and @M.Farooq's answers:
> Is there a good way to systematically increase the accuracy and precision of a measuring tool using only mathematical means?
No, because what you can and should do in terms of maths/statistics depends very much on your application and data generation/measurement pr... |
I'm learning about S and R configuration, and I know that in case where the 4th substituant is not behind we should permute it with the one which is behind. then we find the new configuration and use the opposit, if we find it R then the original configuration is S.
My question concerns the case when should I make 2... |
How do I solve this problem on mass balance from Blast Furnace Iron Making? |
This Thorlabs part [here][1] uses a material that absorbs only NIR and emits in visible. The spec sheets don't list what chemical this is. Do you know materials that have similar properties?
[1]: https://www.thorlabs.com/drawings/acbe94fcb7187ab9-935558D0-050E-5735-7E82B6C05CE5E866/VRC4-SpecSheet.pdf |
In my book it is given that:
The general form of the **grahams law of diffusion** can be stated as follows when one or all of the parameters are varied.
$$rate \propto \frac{PA}{\sqrt{TM}}$$
where P - pressure, A - area of the hole, T- temperature, M- Molecular weight
**Now my doubt:**
How can rate be in... |
Number of planes in $\text{SiH$_2$FCl}$ which contain maximum atoms but all must be different? |
>Number of planes in $\text{SiH$_2$FCl}$ which contain maximum atoms but all must be different?
I am interested in the above problem. I predicted the answer to $10$ which indeed is $5\choose 3$ because maximum number of points in a plane will be $3$ since the structure is tetrahedral. But the book writes an answer $... |
I'm not a chemist at all but I am looking for a specific type of container which I'm sure must exist but I don't know it's name.
We want to store non-toxic (non-cyanide) gold solution for electroplating in a small (10-20ml) transparent container that has an inbuilt, permanent electrode for the plating process:
[!... |
In my book it is given that:
> The general form of the **Grahams Law of Diffusion** can be stated as follows when one or all of the parameters are varied:
$$\text{rate} \propto \frac{PA}{\sqrt{TM}},$$
where $P$ - pressure, $A$ - area of the hole, $T$ - temperature, $M$ - Molecular weight.
How can rate be invers... |
Why is the rate inversely proportional to the square root of temperature in Grahams Law of Diffusion? |
Can somebody explain me the electrolysis of molten $\ce{NaCl}$ via electrode potential?
Reduction potential of $\ce{Cl-}$ is -1.36 V, while sodium metal is -2.76 V, but still sodium is reduced and not $\ce{Cl-}.$ |
### Question
> An ironmaking blast furnace produces hot metal of the composition: $\pu{93.6\%}$ $\ce{Fe},$ $\pu{2.1\%}$ $\ce{Si},$ $\pu{3.6\%}$ $\ce{C},$ $\pu{0.7\%}$ $\ce{Mn}.$ The composition of the iron ore is $\pu{78\%}$ $\ce{Fe2O3},$ $\pu{9\%}$ $\ce{SiO2},$ $\pu{5\%}$ $\ce{Al2O3},$ $\pu{1\%}$ $\ce{MnO},$ $\pu{7... |
How do I solve this problem on mass balance from blast furnace iron making? |
If I were to add an oxidizing agent like dilute Potassium permanganate to a potential fuel such as plastics (polystyrene etc), would the combustion of this fuel be more complete ie: less sooty flame, brighter/hotter flame etc? |
If I were to add an oxidizing agent like dilute Potassium permanganate (aq) to a potential fuel such as plastics (polystyrene etc), would the combustion of this fuel be more complete ie: less sooty flame, brighter/hotter flame etc? |
First off, I've learnt that stronger acids produce weaker conjugate bases (through Brønsted–Lowry acid–base theory).
Then I looked at the $\ce{pKa}$ values of $\ce{HF, HCl, HBr,and HI}$ and came to the conclusion that $\ce{HI}$ is the strongest among them and that explains why $\ce{I^-}$ is the weaker base.
So fa... |
Why exactly is $\ce{F^-}$ a stronger base than $\ce{I^-}$? |
First off, I've learnt that stronger acids produce weaker conjugate bases (through Brønsted–Lowry acid–base theory).
Then I looked at the $\ce{pKa}$ values of $\ce{HF, HCl, HBr,and HI}$ and came to the conclusion that $\ce{HI}$ is the strongest among them and that explains why $\ce{I^-}$ is the weaker base.
So fa... |
First off, I've learnt that stronger acids produce weaker conjugate bases (through Brønsted–Lowry acid–base theory).
Then I looked at the $\mathrm{p}K_\mathrm{a}$ values of $\ce{HF}$, $\ce{HCl}$, $\ce{HBr}$, and $\ce{HI}$ and came to the conclusion that $\ce{HI}$ is the strongest among them and that explains why $\c... |
Why exactly is a fluoride anion a stronger base than iodine anion? |
This is an Ascii table for the elements on the 4th period (row) of the periodic table, and distribution of electrons in each orbit.
+---------+----------+---------+---------+----------+---------+
| | | | | | |
+---------+----------+---------+-------... |
Why is the valency of the Calcium (Ca) Bohr model, set to 2 electrons, instead of 1 electron for stability? |
Which is more acidic HOF or HOCl? |
I'm learning about *S* and *R* configuration, and I know that in case where the 4th substituant is not behind we should permute it with the one which is behind. then we find the new configuration and use the opposit, if we find it *R* then the original configuration is *S*.
My question concerns the case when should ... |
So I have been trying to understand how to draw R and S configurations. I feel like I have understood how to draw them, but every time I do a question, I get a wrong answer.
So here is what I have understood,
1. The lowest priority goes to the back of the compound meaning on the dash line.
2. The highest prior... |
I understand that molecules adsorbed to a coinage metal surface experience plasmonic enhanced Raman shifts and I have a spectrometer that I would like to perform SERS measurements with but do not have a Raman microscope/probe. I do have a light-tight cuvette cell and I am wondering if I could coat the inside of a cuvet... |
Could coating silver inside of a cuvette be used for SERS? |
If I'm drawing a Bohr model of Neon, the middle is the nucleus, the first energy level contains 2 electrons. The second level contains 8 electrons. 8+2= 10, Neon's atomic number. But then what are the atomic orbitals, like s, p, d, and f. Where do they come in? Are they completely different from the energy level? |
What's the difference between atomic orbitals and energy levels? |
In [A Primer on
Quantum Numbers and Spectroscopic Notation
Contents][1], the concept of a term and level is described as
> a) The level is the set of 2J+1 states with specific values of L, S,
> and J. The difference in the energy between two levels gives the
> wavelength or frequency of an atomic transition.
... |
In [A Primer on
Quantum Numbers and Spectroscopic Notation
Contents][1], the concept of a term and level is described as
> a) The level is the set of 2J+1 states with specific values of L, S,
> and J. The difference in the energy between two levels gives the
> wavelength or frequency of an atomic transition.
... |
when potassium dichromate is being used as an oxidising agent, it gets reduced from chromium 6+ to chromium 3+ - s there any way to know that or calculate that other than being familiar with general oxidation states? |
how to know dichromate is being reduced from Cr 6+ to Cr 3+? |
How to formulate the 1 dimensional time-dependent Schrodinger’s equation from a given function? |
> Neon's atomic number. But then what are the atomic orbitals, like s,
> p, d, and f. Where do they come in? Are they completely different from
> the energy level?
Atomic theory was developed in stages almost a century ago. Bohr's model is the simplest version of hydrogen atom. General chemistry textbooks write ra... |
Who are you talking to? To non-chemists (in the US), just say i-oh-dyne.
But if you are talking with chemists, say i-oh-deen.
If you are talking to a mix of chemists and non-chemists, decide which you would like to be classified as.
Or, you could say "element 53". |
The reaction is used industrially to make hydroquinone (source: [wikipedia][1]), but often using hydrogen peroxide as the oxidation agent in the presence of a catalyst.
A [study on catalytic hydroxylation of benzene][2] comes to the following conclusion:
>experimental evidences have allowed first discarding Fento... |
If pressure and temperature are known constants, how can I determine the solubility of a known amount of gas in a mixture of molten salts?
Assume the mixture of salts is homogeneous and the composition (as well as amount of said compounds) is known. |
Since fluorine and pottasium form ions to gain the electronic configuration of Neon and Argon respectively, then shouldn’t $K^+$ have a greater radius, as Argon is larger than helium?
Also which would have a bigger atomic radius, Pottasium or Fluroine? |
Why do $K^+$ and $F^-$ ions have the same ionic radii? |
Since fluorine and potassium form ions to gain the electronic configuration of neon and argon respectively, then shouldn’t $\ce{K+}$ have a greater radius, as argon is larger than neon?
Also which would have a bigger atomic radius, potassium or fluorine? |
> Why do K+ and F− ions have the same ionic radii?
They don't:
[![enter image description here][1]][1]
Source: https://commons.wikimedia.org/wiki/File:Atomic_%26_ionic_radii.svg
[1]: https://i.stack.imgur.com/lOtll.png |
Since fluorine and potassium form ions to gain the electronic configuration of neon and argon respectively, then shouldn’t $\ce{K+}$ have a greater radius, as argon is larger than neon?
Also which would have a bigger atomic radius, potassium or fluorine?
The orignal question is
The ionic radii of K+ and F- ar... |
Since fluorine and potassium form ions to gain the electronic configuration of neon and argon respectively, then shouldn’t $\ce{K+}$ have a greater radius, as argon is larger than neon?
Also which would have a bigger atomic radius, potassium or fluorine?
The original question is
The ionic radii of K+ and F- a... |
Do K+ and F- ions have the same ionic radii? |
Since fluorine and potassium form ions to gain the electronic configuration of neon and argon respectively, then shouldn’t $\ce{K+}$ have a greater radius, as argon is larger than neon?
Also which would have a bigger atomic radius, potassium or fluorine?
The original question is
The ionic radii of $\ce{K+}$ a... |
> Why do K+ and F− ions have the same ionic radii?
They don't according to wikipedia:
[![enter image description here][1]][1]
Source: https://commons.wikimedia.org/wiki/File:Atomic_%26_ionic_radii.svg
They do according to "Data taken from John Emsley, The Elements, 3rd edition. Oxford: Clarendon Press, 19... |
I'm wondering which atomic orbital is left in a quadrupol complex to bind the steric ligand, since all d orbitals except the x2-y2 are used for the metal metal bonds?
or is it the x2-y2 atomic orbital that forms the bonding?
and if so: what atomic orbital is used in metal metal quintuple complexes?
Here is an ... |
What is the binding mode of the ligand in quadrupole complexes? |
I'm wondering which atomic orbital is left in a complex with quadruple metal-metal bond to bind the steric ligand, since all d orbitals except the x2-y2 are used for the metal-metal bonds?
or is it the x2-y2 atomic orbital that forms the bonding?
and if so: what atomic orbital is used in metal-metal quintuple com... |
What is the binding mode of the ligand in complexes with quadruple metal-metal bonds? |
**The technical terms**
> There is no such thing as a most stable resonance structure. – Martin
The correct term would be resonance contributor. All these structures contribute, so the charges are spread over the molecule. Also, formal charges are mostly an accounting scheme. For example in the ammonium ion, most o... |
In [A Primer on
Quantum Numbers and Spectroscopic Notation
Contents][1], the concept of a term and level is described as
> a) The level is the set of 2J+1 states with specific values of L, S,
> and J. The difference in the energy between two levels gives the
> wavelength or frequency of an atomic transition.
... |
> First off, I've learnt that stronger acids produce weaker conjugate bases (through Brønsted–Lowry acid–base theory).
That is correct.
> Then I looked at the $\mathrm{p}K_\mathrm{a}$ values of $\ce{HF}$, $\ce{HCl}$, $\ce{HBr}$, and $\ce{HI}$ and came to the conclusion that $\ce{HI}$ is the strongest among them a... |
I was surprised to find out that the zero-point energy (ZPE) for the ground state of BH$_3$ is around 17000 cm$^{-1}$, because for molecules I usually work with, it's much smaller. Does anyone know the largest recorded ZPE?
I have recently asked a similar question: https://chemistry.stackexchange.com/questions/11954... |
What is the largest known zero-point energy for a molecule? |
I was surprised to find out that the zero-point energy (ZPE) for the ground state of BH$_3$ is a few thousand cm$^{-1}$, because for molecules I usually work with, it's much smaller. Does anyone know the largest recorded ZPE?
I have recently asked a similar question: https://chemistry.stackexchange.com/questions/119... |
A volumetric flask has an uncertainty of ±0.150 so should the number of significant figures after the decimal point in my final answer be three or two? |
this is a gold bar. If we look at its structure, will we see that there are atoms that have a different number of neutrons (aka isotopes) (as far as I'm concerned, an isotope is an atom with a different amount of neutrons in it)
or has it to be another bar that consists of this isotopes? |
Whenever my textbook used this statement all that they have done is the inverse of what we used to do when we had to calculate the content of a particular element in a compound (for example parts of $Fe$ in $Fe_2O_3$). In such problems we used to get things like (Wt of Fe)/(Wt of Fe)+(Wt of FeO).Now in this case they h... |
What is the physical meaning of the statements like "FeO in the form of Fe" in directly reduced iron? |
Aluminum resists corrosion in neutral or slightly off-neutral water because of the very insoluble Al2O3 film on the metal. If you break this film, it will corrode the bare metal and reform.
But if you scratch the Al and attach a cathode (a less active metal), you have a galvanic cell, and H2 can be evolved from this... |
On our exam in organic chemistry, there was a question that I failed to answer correctly. The question is about the Baeyer-Villiger Esterification of propiophenone or ethyl phenyl ketone:
[![enter image description here][1]][1]
On the exam, I answered this structure:
[![enter image description here][2]][2]
... |
Where will the Oxygen atom be inserted on the Baeyer-Villiger Esterification? |
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