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My local newspaper ran an article covering the local rules about fireworks. One of those rules specifically calls out "snakes and fountains containing mercury bichloride" as forbidden.
Neither Wikipedia's article on [mercury(II) chloride][1] nor its article on [mercury][2] lists any fireworks-related use. What pur... |
What purpose does mercury bichloride have in fireworks? |
Not really a chemistry question since no reactions happening, but couldn't find a more appropriate stack exchange site.
Considering recycling aluminum cans for scrap metal using induction heating. I've seen people do it with very unsophisticated equipment, but what I don't get is Al2O3 is denser (3.95g/mL) than molt... |
does aluminum oxide float on molten aluminum and by what mechanism? |
I will measure absorbance for measurement of protein concentration.
The sample solutions are prepare in serial dilutions to the volume of 100 uL to obtain a certain concentration of the protein in the buffer, lets say 2 mg/mL, then 20 uL is added to the cuvette with 1 mL Bradford reagent.
Now my question is, is t... |
How do I calculate the correct sample concentration for my measurements? |
Hello someone please help! I've learmed that in gas our solute can only be a gas is that correct? How about water in gas is that liquid in gas or gas in gas? |
Is water in air liquid in gas? |
The size of an anion is greater compared to its parent atom because former's effective nuclear charge is lesser than that of latter.
I found on [wikipedia][1] that the effective nuclear charge can be calculated by the formula:
**Zeffective = No. of protons in the nucleus - No. of non-valence electrons**
**For ... |
> should I recalculate the dilutions to get the concentration 2 mg/mL in total with the reagent added?
Either way works as long as you are consistent.
**Plot dilute concentration**
You can use the final concentration in the cuvette and plot this against the measured absorbance. When you use this standard curve... |
My local newspaper ran an article covering the local rules about fireworks. One of those rules specifically calls out "snakes and fountains containing mercury dichloride" as forbidden.
Neither Wikipedia's article on [mercury(II) chloride][1] nor its article on [mercury][2] lists any fireworks-related use. What pur... |
What purpose does mercury dichloride have in fireworks? |
How to account for solvation of a molecule explicitly in quantum calculation? |
My local newspaper ran an article covering the local rules about fireworks. One of those rules specifically calls out "snakes and fountains containing mercury bichloride" as forbidden.
Neither Wikipedia's article on [mercury(II) chloride][1] nor its article on [mercury][2] lists any fireworks-related use. What pur... |
To how much significant figures do I reduce my absolute uncertainty if it has more significant figures than my measurement? |
I've learned that in a gas, the solute has to be a gas a well. Is that always the case? How about water in air, is that liquid in a gas, or a gas in a gas? |
Does water in air occur as liquid or as gas? |
How could I prepare Iron(III) arsenate (FeAsO4)? |
> ... my main concern is the energy part. Where does electron get the energy to revolve in a shell?
M. Farooq's answer makes the analogy with planetary motion. Continuing the analogy, where did our planet earth get the energy to revolve around the sun? We don't really know, but we know that there is potential energy... |
The structure contains 4 independent atoms, Mg, Al, Si and O. The space group is a cubic one, with 48 asymmetric units in them. If you place an atom on a general position, it will appear 48 times in the unit cell. Mg, Al, and Si are located in various special positions, i.e. lie on symmetry elements. Placing one Mg and... |
The structure contains 4 independent atoms, Mg, Al, Si and O. The space group is a cubic one, with 48 asymmetric units in them. If you place an atom on a general position, it will appear 48 times in the unit cell. Mg, Al, and Si are located in various special positions, i.e. lie on symmetry elements. Placing one Mg and... |
**How do I get into method development?**
As was said in the comments, one would join a group that works in this field and learn from them. From up close, there is some derivation from previous results and some trial and error involved. And yes, a PhD-sized investment is typically required.
**How do I get into me... |
The structure contains 4 independent atoms, Mg, Al, Si and O. The space group is a cubic one containing 96 asymmetric units. If you place an atom on a general position, it will appear 96 times in the unit cell. Mg, Al, and Si are located in various special positions, i.e. lie on symmetry elements. Placing the Mg and th... |
I Found on web video make me wondering what the hack is this , how its even possible ,so any one know what is happen can explain to me please
https://www.youtube.com/watch?v=B_olJLjgcHc |
wonder how its work and get heat red mercury? |
> Is Wikipedia's use of "quasi" in the title for the enzyme kinetics reflective of [...] the further assumption that $[S]$ is constant[...]?
No I don't think the "quasi-steady state" hypothesis is related to whether $[S]$ varies with time.
>[W]hy add a further descriptor that denotes uncertainty or inaccuracy w... |
Activated carbon (AC) is one of the most widely used media for water filtration. It's effective at removing chlorine taste and odor, and it's recognized as being safe.
However, most activated carbon filters have an indicated lifespan of about 4-6 months, after which they need to be replaced. But is there any risk to... |
there is a problem regarding a Diels-Alder reaction that I do not understand (see image).
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/Ratbj.png
The Diels-Alder reaction of the diene and the dienophile should lead to the product A. I hope I did it correctly, because the molecular fo... |
> The size of an anion is greater compared to its parent atom because former's effective nuclear charge is lesser than that of latter.
This is not the best explanation. The size of the anion is larger because, as Poutnik wrote in the comment, the effective nuclear charge is almost the same (if you account for nuclea... |
In high school, I am taught that the synthesis of two amino acids of the form $\ce{H2NR1COOH}$ and $\ce{H2NR2COOH}$ is a condensation reaction that produces a polypeptide $$\ce{H2NR1COOH}+\ce{H2NR2COOH}\to\ce{H2NR1CONHR2COOH}+\ce{H2O}$$ where $\ce{R1}$ and $\ce{R2}$ are arbitrary components within each acid. Then I sta... |
Are these chemical reactions with amino acids possible, and if so, what are they called? |
How was this fake red mercury video made? |
The reduction potentials of $\ce{ClO_4^-, ClO_3^-, HClO_2, and ClO_2}$ in acidic solution are $1.19, 1.21, 1.65$, and $1.63$, and in basic solution are $0.56, 0.63, 0.78$ and $0.89$ volts, respectively.
Why is $\ce{ClO^-}$ such a strong oxidizing agent compared to other chloride oxyanions, despite its low oxidation ... |
Why is hypochlorite a stronger oxidizing agent than other oxychlorides? |
How to increase CO2 gas in club soda... I am planning to start a pet bottled club soda industry... My process involves chilling the water up to about 4°C and filling under pressure up to 4.5 bar.... Of course, once the bottle is filled, pressure will be released to facilitate capping. That is the standard procedure to ... |
The reduction potentials of perchlorate, chlorate, chlorous acid and chlorine dioxide in acidic and basic solutions are listed in the table below:
$$
\begin{array}{lcc}
\hline
\text{Oxychloride} & E^\circ_\text{acidic}/\pu{V} & E^\circ_\text{basic}/\pu{V} \\
\hline
\ce{ClO4-} & 1.19 & 0.56 \\
\ce{ClO3-} & 1.21 &... |
Since you actually considered the use of a calutron, I assume that you are interested in separation of relatively small amounts of pure ZnO - on the order of a few grams.
Cadmium and zinc are similar in many respects, which makes me think of rare earths. One of the separation techniques used there is ion exchange ch... |
Can you plausibly extract Oxygen from Iron Oxide (aka Rust) with Sodium Chloride? |
How to increase CO2 gas in club soda... I am planning to start a PET bottled club soda industry... My process involves chilling the water up to about 4°C and filling under pressure up to 4.5 bar.... Of course, once the bottle is filled, pressure will be released to facilitate capping. That is the standard procedure to ... |
> Is there any harm involved in keeping copper water bottles in fridge/refrigerator?
Few days back, in summer, I carried [kokum](https://en.wikipedia.org/wiki/Garcinia_indica) [juice](https://www.amazon.in/Mapro-Kokum-Crush-1L/dp/B01N3UNHW3) in copper bottle. I had a sip of it after some time when I reached office a... |
I have 50 ml of a compound I would like to purify. Since the impurities presents have close boiling points (b.p.), I have to use fractional distillation. Am I going to lose significant quantity of my product volume because of loss related to the distillation itself?
If so, what can I do to minimize the loss?
I th... |
This reaction isn't feasible and won't likely occur.
## Why not? ##
Rust and Salt are very stable, and happy with their current state. You can see this better by looking at each product.
Rust forms from Iron and Oxygen
> 4Fe + 3O2 → 2Fe2O3
Salt is formed from Sodium and Chlorine
> Na + Cl → NaCl
T... |
How to increase $\ce{CO2}$ gas in club soda? I am planning to start a PET bottled club soda industry. My process involves chilling the water up to about $\pu{4 °C}$ and filling under pressure up to $\pu{4.5 bar}$. Of course, once the bottle is filled, pressure will be released to facilitate capping. That is the standar... |
Is activation energy equivalent to Gibbs Free Energy of transition state as related by Eyring equation?
$$E_a=\Delta ^\ddagger G \, \, ?$$
Is Gibbs Free Energy of transition state defined by the Gibbs Free Energy of formation?
$$\Delta ^\ddagger G :=\Delta _\mathrm{f} G \, \, ?$$
If not, which are the conditions ... |
Is Gibbs Free Energy of formation equal to Gibbs Free Energy of transition state? |
I Understand how a single galvenic cell works , and the relation of equilibrium and the nernst equation .
But this appears to contradict the higher voltage in a series configuration because it basiclly tells you there is a limit of how much excess charges can the plates build up before the reactions halts , So how ... |
There are two parts of your question. We should not mix historical medical practices with modern scientific *truths*. Also, this does not mean that all old medical knowledge is bad or useless. In older medicine, gold foil arsenic compounds, silver foil, crushed pearls and mercury oxides were added in medicines,. It d... |
Voltage and (thermodynamic) electrode potential are slightly different things. Electrode potential refers to the maximum amount of work that can be extracted from a given *single* cell under very specific conditions and at a given concentration of metal ions.
Now forget about the cells shown in chemistry textbooks. ... |
The trick is a very basic physical intuition error - one that one should not be blamed for, because it took the likes of Galileo and Newton to realize what was wrong with it, and as an idea it held as orthodoxy for ages and across the world prior to the innovations of their genius. It's much like the Flat Earth - there... |
I Understand how a single galvanic cell works , and the relation of equilibrium and the nernst equation .
But this appears to contradict the higher voltage in a series configuration because it basiclly tells you there is a limit of how much excess charges can the plates build up before the reactions halts , So how ... |
The key point is [estimation of standard deviation of estimation of measurement standard deviation on Stats SE](https://stats.stackexchange.com/questions/631/standard-deviation-of-standard-deviation).
The exact formula is complicated with extensive Gamma function involvement.
The essential info is the relative unc... |
I want to learn to develop novel methods in computational chemistry (e.g. Grimme's empirical dispersion, DFTB, new DFT functionals, etc.) What is the ideal way to learn this by oneself?
I have read books on the Hartree-Fock theory and I understand it to some degree. However, there seems to always be a large amount o... |
> Does chilling drinking water in copper bottle result in any chemical reaction that turns it dangerous for consumption in any way?
Few days back, in summer, I carried [kokum](https://en.wikipedia.org/wiki/Garcinia_indica) [juice](https://www.amazon.in/Mapro-Kokum-Crush-1L/dp/B01N3UNHW3) in copper bottle. I had a s... |
I have been doing some experiments concerning bleaching of chlorophyll stains from cotton clothing. Currently I have found that H2O2 is fairly effective, but still leaves visible stains. Would a crude Horseradish Root extract containing Peroxidase get me better results? The reason I'm asking about the crude extract and... |
I read that the equilibrium constant is unitless because the molar activities of each of the species are used in the equilibrium expression, not the actual concentrations themselves. I understand that.
But it is taught that
$$K_c = \frac{k_\mathrm{fwd}}{k_\mathrm{rev}}$$
I’m having some difficulty understandin... |
I have been doing some experiments concerning bleaching of chlorophyll stains from cotton clothing. Currently I have found that $\ce{H2O2}$ is fairly effective, but still leaves visible stains. Would a crude [Horseradish](https://en.wikipedia.org/wiki/Horseradish) root extract containing peroxidase get me better result... |
The substrate you have provided (2-butanol) would indeed give a positive test.
The iodoform test is performed in presence of iodine and potassium or sodium hydroxide, which first oxidizes the aforesaid compound to 2-Butanone.
**Mechanism** (taken from [this Wikipedia page](https://en.wikipedia.org/wiki/Haloform_... |
Why does Freundlich adsorption isotherm not have a term for surface area?
The formula given by Freundlich adsorption isotherm:
>$$ \frac{x}{m}= k P ^{1/n}$$
>Where $x$ is the mass of gas adsorbed on mass $m$ of the adsorbent and pressure $P$. $k$ and $n$ are constants which depend on the nature of the absorben... |
Why does Freundlich adsorption isotherm not have a term for surface area? |
> The size of an anion is greater compared to its parent atom because former's effective nuclear charge is lesser than that of latter.
This is not the best explanation. The size of the anion is larger because, as Poutnik wrote in the comment, the effective nuclear charge is almost the same (if you account for nuclea... |
I understand how a single galvanic cell works, and the relation of equilibrium and the Nernst equation.
But this appears to contradict the higher voltage in a series configuration because it basically tells you there is a limit of how much excess charges can the plates build up before the reactions halts, So how doe... |
A friend of mine performed a standard synthesis reaction of *Potassium Dioxalatodiaquochromate (iii)*, by adding *potassium dichromate* to *ethandioic acid dihydrate* and a little water, and the synthesis instructions suggested that only the cis- form is created. When looking online about this, I found numerous dodgy d... |
Why does only the cis-isomer of potassium dioxalatodiaquochromate (iii) form? |
I haven't been able to find any literature on $\ce{^{19}F}$ solid state NMR studies of $\ce{LiF}$ crystals, not even $\ce{LiF}$ powders. Is there any NMR chemists who is familiar with $\ce{LiF}?$ Any references are greatly appreciated. |
A friend of mine performed a standard synthesis reaction of potassium dioxalatodiaquochromate(III) by adding potassium dichromate to ethandioic acid dihydrate and a little water. The synthesis instructions suggested that only the *cis*-form is created. When looking online about this, I found numerous dodgy documents co... |
Why does only the cis-isomer of potassium dioxalatodiaquochromate(III) form? |
UV/Vis Spectroscopy is where electromagnetic radiation in the UV to Visible range is shone at a sample to be analysed. The absorbance of each wavelength is recorded and then plotted (very similar to Infrared spectroscopy). That's why it surprised me so much.
[![enter image description here][1]][1]
This graph is s... |
On adding $\ce{NaCN}$ to $\ce{RX} , we get
$$\ce{NaCN + RX -> RCN +NaX}$$
And not $\ce{RNC}$ Clayden gives the explanation as follows.
> The most important carbon nucleophile with a lone pair of electrons is the cyanide ion. Although linear cyanide (which is isoelectronic with $\ce{N2}$ ) has a lone pair on nitroge... |
On adding $\ce{NaCN}$ to $\ce{RX}$ , we get
$$\ce{NaCN + RX -> RCN +NaX}$$
And not $\ce{RNC}$ Clayden gives the explanation as follows.
> The most important carbon nucleophile with a lone pair of electrons is the cyanide ion. Although linear cyanide (which is isoelectronic with $\ce{N2}$ ) has a lone pair on nitrog... |
On adding $\ce{NaCN}$ to $\ce{RX}$ , we get
$$\ce{NaCN + RX -> RCN +NaX}$$
And not $\ce{RNC}$ Clayden gives the explanation as follows.
> The most important carbon nucleophile with a lone pair of electrons is the cyanide ion. Although linear cyanide (which is isoelectronic with $\ce{N2}$ ) has a lone pair on n... |
On adding $\ce{NaCN}$ to $\ce{RX}$, we get
$$\ce{NaCN + RX -> RCN + NaX}$$
And not $\ce{RNC}$. Clayden gives the explanation as follows:
> The most important carbon nucleophile with a lone pair of electrons is the cyanide ion. Although linear cyanide (which is isoelectronic with $\ce{N2}$) has a lone pair on n... |
Making oxygen from iron oxide (aka rust) with sodium chloride? |
[![Sesamolin][1]][1]
Would all of the Hs in an NMR of this molecule (sesamolin; shown above) be non-equivalent to each other? So even for the 2 Hs at A, they would be non-equivalent to each other.
Follow up question (about a different molecule that is similar): for sesamin shown below, would there be 8 peaks i... |
I understand how a single galvanic cell works, and the relation of equilibrium and the Nernst equation.
[![Normal and "improved galvanic cell"][1]][1]
But this appears to contradict the higher voltage in a series configuration because it basically tells you there is a limit of how much excess charges can the pl... |
The point is not really whether chloride or ammonia is a strong or weak field ligand, the point is $\ce{Co^3+}$ is $\mathrm{d^6}$, and virtually all "octahedral" $\mathrm{d^6}$ complexes are low spin - essentially some complexes of $\ce{Fe^2+}$ and a very small number of fluoro complexes of $\ce{Co^3+}$ are the only e... |
I melted down some table salt and used high voltage welder power source to try and seperate the sodium and chlorine it was partially successful because I could smell and see chlorine gas but during the reaction what I think was sodium would float to the top of the molten salt and burst into flame. Is there a way to pre... |
Is it possible to make crepe rubber from
combining a synthetic rubber emulsion (Styrene Butadiene Emulsion)
and a strong acid? |
On adding $\ce{NaCN}$ to $\ce{RX}$, we get
$$\ce{NaCN + RX -> RCN + NaX}$$
And not $\ce{RNC}$. Clayden gives the explanation as follows:
> Although linear cyanide (which is isoelectronic with $\ce{N2}$) has a lone pair on nitrogen and a lone pair on carbon, the nucleophilic atom is usually anionic carbon rathe... |
First, sodium burns very nicely in air. However, it also burns in chlorine, returning back to the $\ce{NaCl}$.
Most welders provide *alternating* current, meaning the the electrode becomes alternately positive and then negative (50 times per second (50 Hz) in much of the world, and 60 Hz in North America). Therefore... |
[![**enter image description here**][1]][1]
[1]: https://i.stack.imgur.com/Sc8BK.png
(2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanal
(2R,3S,4R)-2,3,4,5-tetrahydroxypentanal
I really couldn't think of a feasible test to differentiate the two since they only differ in the number of Cs, which I think do not en... |
What reagent/s could one use to distinguish pentanal from hexanal? |
I understand how a single galvanic cell works, and the relation of equilibrium and the Nernst equation.
[![Normal and "improved galvanic cell"][1]][1]
But this appears to contradict the higher voltage in a series configuration because it basically tells you there is a limit of how much excess charges can the pl... |
How to know if a nucleophile will attack from front-side(retention of configuration) or back-side(inversion of configuration) in sn2 reaction? |
How to know if a nucleophile will attack from front-side or back-side in a reaction? |
I understand how a single galvanic cell works, and the relation of equilibrium and the Nernst equation.
[![Normal and "improved galvanic cell"][1]][1]
or
[![Galvenic cell in series (using salt bridge)][2]][2]
But this appears to contradict the higher voltage in a series configuration because it basically tel... |
I understand how a single galvanic cell works, and the relation of equilibrium and the Nernst equation.
[![Galvenic cell in series (using salt bridge)][2]][2]
But this appears to contradict the higher voltage in a series configuration because it basically tells you there is a limit of how much excess charges can th... |
How to know if a nucleophile will attack from front-side or back-side in a sn2 reaction? |
How to know if a nucleophile will attack from front-side(retention of configuration) or back-side(inversion of configuration) in sn2 reaction?
https://www.youtube.com/watch?v=L01vv1Mj64I
In this video same reaction is showing both frontside and backside. |
[![Sesamolin][1]][1]
Would all of the Hs in an NMR of sesamolin (5-{(1*S*,3a*R*,4*R*,6a*R*)-4-[(2*H*-1,3-benzodioxol-5-yl)oxy]tetrahydro-1*H*,3*H*-furo[3,4-*c*]furan-1-yl}-2*H*-1,3-benzodioxole; shown above) be non-equivalent to each other? So even for the two Hs at A, they would be non-equivalent to each ... |
Methane $\ce{CH4}$ is symmetrical and non polar, and so is oxygen $\ce{O2}$. But $\ce{O2}$ doesn't absorb IR. Why is that? People say that if a molecule can change its polarity then it will absorb IR, but I don't understand how a molecule changes its polarity while absorbing IR.
Please try to keep your answer simp... |
Why are some molecules unable to absorb infrared radiation? |
Besides the the thermodynamic aspects discussed by Matthew, consider the kinetic aspects. Oxidation by a chlorine oxyanion involves displacenent of oxygen from its bond with the chlorine. Such a displacement, in a protic solvent such as water, must involve protonation of the oxygen:
* Oxygen without the proton wo... |
Which one of the following is strongest base?
A.Cl-
B.Br-
C.I-
D.CH3COOH
Someone please tell me the answer with proper reason. |
Which one of the following is strongest base?
A.Cl-
B.Br-
C.I-
D.CH3COOH-
Someone please tell me the answer with proper reason.
First I thought that it's Cl but then it clicks in my mind no it's CH3COOH cuz it's conjugate base of weak acid.. |
> Which one of the following is strongest base?
> **A**. $\ce{Cl-}$
> **B**. $\ce{Br-}$
> **C**. $\ce{I-}$
> **D**. $\ce{CH3COO-}$
Someone please tell me the answer with proper reason.
First I thought that it's $\ce{Cl-},$ but then it clicks in my mind that it's $\ce{CH3COO-}$ since it's a conjugate ... |
You actually got it! I assume you're taking this for General Chemistry, right?
Anyway, that is exactly the reason. The proper way to get to the (right) answer is to ask yourself which one is the conjugate base of a weak acid. If you are given more than one weak acid, you should be provided with the respective acidic c... |
H2O2 is Selective
The reason why hydrogen peroxide can be used for such diverse applications is the different ways in which its power can be directed -- termed selectivity. By simply adjusting the conditions of the reaction (e.g., pH, temperature, dose, reaction time, and/or catalyst addition), H2O2 can often be mad... |
Why do we not talk about entropy when deciding feasibility of an organic reaction?...We always seem to only be interested in stability of product and intermediate(essentially delta H)and draw their respective graphs of Delta H of the reaction showing the peak of intermediate..shouldn't we look at delta G? |
Why do we not talk about entropy when deciding feasibility of an organic reaction?...We always seem to only be interested in stability of product and intermediate(essentially delta H)and draw their respective graphs of Delta H of the reaction showing the peak of intermediate..shouldn't we look at change in Gibbs free ... |
We know that one definition of boiling point is that it's the temperature at which the vapor pressure is same as the atmospheric pressure.
Assuming a closed container, does that mean that at this temperature, the total pressure exerted on the liquid is twice the atmospheric pressure, i.e., the vapor pressure plus th... |
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