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1answer
52 views

Friedel-Crafts Alkylation of Pyrrole [duplicate]

I thought that I already know how the Electrophilic Aromatic Substitution (EArs) for Aromatic rings work but then this reaction was shown to me and I was really sure that my professors didn't bothered ...
1
vote
2answers
102 views

Is there any mathematical or logical proof that carbon with 4 different groups would be chiral?

In chemistry; chirality is generally defined in 2 ways. Lord Kelvin's definition: "I call any geometrical figure, or group of points, chiral, and say it has chirality, if its image in a plane mirror,...
1
vote
0answers
14 views

Unable to find time required to reach adsorption equilibrium

Did an experiment on ZIF-8 dye adsorption, we had to find the relationship between reaction (stirring) time and adsorption performance. 20mg of ZIF-8 mixed with 10mL of Methyl blue (concentration: $...
0
votes
1answer
57 views

Why does period 3 of the periodic table contain 8 elements instead of 18?

Period 1 of the periodic table contains 2 elements ($1s^1$ and $1s^2$). Period 2 contains 8 elements ($2s^1$, $2s^2$, $2p^1$, $2p^3$, ..., $2p^6$). By the same argument, period 3 might contain 18 ...
1
vote
0answers
22 views

Is bonds in CO is all 3 coordinate bonds or 2 covalent and 1 coordinate bonds?

Below image is as available in India's Class 11 NCERT Chemistry book vol 1 Page 104. I am confused as it states all 3 bonds are kind of coordinate bonds. Should it not start with 2 covalent bonds and ...
0
votes
1answer
61 views

Neutralization between Ca(OH)2 + H2SO4 in a 30% hydrogen peroxide solution

I have performed an experiment where I added an excess of $\ce{Ca(OH)2}$ base to a solution consisting of 5 mL of 30 % hydrogen peroxide (buffered at pH 5) and a very small amount of sulfuric acid (...
4
votes
0answers
122 views

What is the dataset with the largest number of molecules?

In computational chemistry we often apply techniques to all molecules of a "dataset". Recently it was asked which dataset contains the largest molecules, and a user accidentally misinterpreted this ...
4
votes
1answer
86 views

Why is only the carbonate anion used to precipitate Barium?

Q: Why is the $\ce{CO3^2-}$ anion used to precipitate Barium from $\ce{BaBr2}$ and not another anion, such as $\ce{PO4^3-}$, or $\ce{SO4^2-}$? I am studying high school Chemistry, and the current ...
0
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0answers
25 views

Alcohol Nonmeclature - Organic Chemistry

I'm new to organic chemistry and having some trouble naming alcohols. I came across this molecule, I believe it's name is 3-ethyl 2-pentanol, but my online checker system is saying that I am wrong. Am ...
12
votes
3answers
799 views

What are datasets containing molecules with more than 38 heavy atoms?

I have been testing a machine learning approach for molecular energy prediction. The current dataset that I have is QM9, which is consist of molecules with up to 9 heavy atoms. I was wondering if ...
-3
votes
0answers
24 views

Isomer of complex compound [closed]

I've got question about isomers in complex compounds. What is the connection isomerism of complex compounds? Maybe somebody can explain and give me some examples.
-2
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0answers
46 views

How are salts isolated from an acid?

I am curious in the production of salts (specifically stannous chloride and palladium chloride) by dissolving the metals in $\ce{HCl}$ in stoichiometric amounts: $$\ce{Sn (s) + 2HCl (aq) -> SnCl2 (...
2
votes
0answers
41 views

Where will the oxygen atom be inserted on the Baeyer-Villiger esterification? [duplicate]

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: On the exam,...
-1
votes
1answer
50 views

What is the physical meaning of the statements like “weight percentage of FeO in Fe”? [closed]

I have always had the notion of calculating weight percentage of Fe in FeO. It always seems that we are to calculate at times the weight percentage of FeO in Fe.Particularly when one weight percentage ...
-3
votes
1answer
57 views

Isotopes and elements [closed]

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 ...
-3
votes
1answer
51 views

Significant figures and uncertainty [closed]

A narrow-necked volumetric flask with a capacity of 200mL has an uncertainty of ±0.150mL so should the number of significant figures after the decimal point in my final answer be three or two?
2
votes
0answers
67 views

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 $\ce{BH3}$ is a few thousand $\pu{cm-1}$, because for molecules I usually work with, it's much smaller. Does anyone ...
0
votes
1answer
32 views

What is the binding mode of the ligand in complexes with quadruple metal-metal bonds?

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 ...
-1
votes
0answers
20 views

What is the correct order of ionization energies of fluorine, chlorine, and their corresponding anions [duplicate]

What I feel, is that the fluorine and chlorine anions have extremely stable configurations so their ionization energies must be the greatest. And since $\ce{F}$ is smaller than $\ce{Cl}$, it will ...
-1
votes
1answer
56 views

Do K+ and F- ions have the same ionic radii? [closed]

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 ...
2
votes
1answer
48 views

Determining solubility of a gas in a molten salt [closed]

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 ...
-2
votes
2answers
50 views

How to know dichromate is being reduced from Cr⁶⁺ to Cr³⁺?

When potassium dichromate is being used as an oxidising agent, it gets reduced from chromium(VI) to chromium(III). Is there any way to know that or calculate that other than being familiar with ...
0
votes
0answers
33 views

Why chemicals bottles (plastic) have paper seals?

I have my film developer and fixer in the plastic bottles, also I have glycerine and propylene glycol. They all have paper seals (in caps) that those chemicals get wet and destroy - they just fell ...
11
votes
2answers
168 views

Terminology of atomic spectroscopy: Difference Among Term, States and Level

In A Primer on Quantum Numbers and Spectroscopic Notation Contents, 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. ...
0
votes
1answer
31 views

What's the difference between atomic orbitals and energy levels? [duplicate]

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 ...
0
votes
0answers
35 views

Supposed low temperature CaC2 synthesis

I came across an interesting reaction on allreactions.com under silicon tab: SiO2 + 5C(coke) + CaO = Si + CaC2 + 3CO (800-1000°C) Unfortunately the website doesn't provide sources and I wanted to read ...
2
votes
0answers
29 views

Could coating silver inside of a cuvette be used for SERS?

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 ...
-1
votes
0answers
31 views

Understanding sodium hydroxide reaction with silver nitrate (Metal aquo complexes?) [duplicate]

I'm having trouble understanding why this particular reaction occurs, as it does here, and help would be greatly appreciated. In creating Tollens' reagent, where you mix sodium-hydroxide with silver-...
0
votes
1answer
51 views

Which is more acidic HOF or HOCl?

My attempt to the question: We know that more polar the $\ce{O-H}$ bond, the more acidic is the compound. According to electronegativity, the $\ce{O-H}$ bond of $\ce{HOF}$ should be more polar than $\...
0
votes
1answer
30 views

Why is the valency of the Calcium (Ca) Bohr model, set to 2 electrons, instead of 1 electron for stability? [duplicate]

This is an Ascii table for the elements on the 4th period (row) of the periodic table, and distribution of electrons in each orbit. ...
1
vote
2answers
62 views

Why exactly is a fluoride anion a stronger base than iodine anion? [closed]

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 $\ce{HF}$, $\ce{HCl}$, $\...
-1
votes
1answer
39 views

Using an oxidizing agent to improve combustion of a fuel [closed]

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 ...
-2
votes
1answer
67 views

Electrolysis of molten sodium chloride [closed]

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 ...
1
vote
0answers
20 views

Permanent storage container with electrode for electroplating

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 ...
2
votes
1answer
49 views

Number of planes with maximum atoms

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 $5\choose 3$ ...
2
votes
1answer
32 views

Why is the rate inversely proportional to the square root of temperature in Grahams Law of Diffusion?

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: $$\text{rate} \propto \frac{PA}{\sqrt{TM}},$$ ...
3
votes
1answer
68 views

Material that absorbs only in NIR and emits in visible

This Thorlabs VRC4 card here 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 show similar emission properties ...
0
votes
1answer
57 views

How do I solve this problem on mass balance from blast furnace iron making?

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 ...
1
vote
1answer
33 views

When to permute two times to find optical configuration [closed]

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 ...
8
votes
1answer
97 views

What is the mechanism of oxidation of phenol to benzoquinone?

I looked up the mechanism in a lot of organic chemistry books, including Clayden, Klein, Solomons, McMurry but I couldn't find the mechanism of oxidation of a phenol. I also looked it up in ...
3
votes
2answers
29 views

Can mechanical agitation increase the reaction rate?

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 ...
-4
votes
0answers
48 views

Where are the hydroxyl ions going?

We write $$[\ce{H^+}]\cdot [\ce{OH^-}] = 10^{-14}$$ in aqueous solution. When I add acid, the $[\ce{H^+}]$ will go up then $[\ce{OH^-}]$ will decrease to maintain the constant product, but where ...
0
votes
1answer
57 views

What is the hybridization of chromium in chromate and dichromate ions?

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 ...
0
votes
0answers
14 views

Isotropic nature of Amorphous solid

Check the answer given by Divyansh Jain I am writing this because I am not permitted to comment in that post. Using Divyansh's idea, How can the physical properties be same in amorphous solid if ...
2
votes
0answers
66 views

How to formulate the 1 dimensional time-dependent Schrodinger’s equation from a given function?

Assuming $f(t) =e^{−iωt}$, formulate the 1 dimensional time-dependent Schrodinger’s equation. I started solving the problem as \begin{align} E &= hf, \tag1\label{eq:1}\\ E &= ħw, \tag2\...
-2
votes
0answers
34 views

Why some compound smell and some not ,what is role of chemistry in it [duplicate]

I was performing an experiment in my high school lab regarding test of inorganic salt,i rub the salt on palm with water it smell like vinegar ,where i take another salt and rub with water it didnt ...
1
vote
0answers
24 views

Copper Tetrafluoroborate neutralisation/precipitation to reduce landfill [closed]

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 ...
0
votes
2answers
33 views

How to find the temperature relationship between the isotherms in a compressibility factor (Z) vs pressure graph?

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. Now, suppose we ...
0
votes
0answers
39 views

Comparing dipole moments of Ortho,para and meta compounds

I was doing some questions based on dipole moment ortho,met and para compounds. I was not able to understand why dipole moment for \ce{C6H4NH2NO2} increases from ortho to para Because i think \ce{NH2} ...
6
votes
4answers
541 views

accurate measurement from inaccurate tools [closed]

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 ...

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