Questions tagged [reference-request]
This tag is for questions looking for a single specific, or a small number of (citable) references.
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Meaning of equivalents in organic synthesis
The use of "equivalents" as used in titrations/chemical analysis is an obsolete concept except in some countries. The original meaning of equivalent weights is the weight of a compound that ...
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Does chromium(III) oxide react with or dissolve in liquid sulfur dioxide?
Liquid $\ce{SO2}$ (b.p. −10 °C) is known as a versatile solvent (yet not particularly pleasant to work with) for a wide range of organic and inorganic compounds having limited solubility in ...
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Online catalog of reactions [duplicate]
For a software project, I am looking for online resources about reactions.
The idea is that given some chemical entity, I want to find the reactions it takes part in. For example, given CO, I would ...
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Searching for evidence-based published study that compares disinfectant residues after evaporation
I've been plowing through databases to find evidence-based research reporting on the residue remaining after evaporation of chemical disinfectants. I want to know if there is a study which states the ...
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Density range of table salt?
Does anyone have a reference for the density range of common table salt $(\ce{NaCl})?$
A pure $\ce{NaCl}$ crystal has a density of $\pu{2.16 g/cm^3}.$ However, the salt granules in table salt don't ...
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Do symmetric hydrogen bonds in neutral molecules exist?
As far as I know, there have only few truly symmetric hydrogen bonds been observed. Unquestionable is the existence of it in the bifluoride ion, $\ce{[F-H-F]-}$, see also here. There are a couple of ...
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What does the word "dynamics" mean in the context of proteins or biomolecules in general?
What does it mean by “dynamics” when we say “dynamics of protein” or “dynamics of biomolecules”? For instance, McCammon's paper has the title "Protein Dynamics" [1]. What does the word “...
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IR spectra database for inorganic compounds
I would need a database of IR spectra of inorganic compounds, possibly free of charge. For organic compounds there is for example "AIST: Spectral Database for Organic Compounds, SDBS" (https:...
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Can anisole be nitrated only with nitric acid?
Is it possible to nitrate anisole using only concentrated nitric acid? Or is it necessary to use sulfuric acid or acetic anhydride? Could you please help me with some references?
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How does coenzyme A produce proton from pyruvate ions?
Coenzyme A (CoA) is a complex molecule consisting of mercaptamine, β-alanine, pantoic acid, diphosphate, pentose, phosphate and adenine moieties:
Which part of it actually plays role in the formation ...
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Mathematical models of Vaporization-Condensation dynamics
I am a mathematician now studying an introductory chemistry course.
Consider a liquid in a closed container, at (say) room temperature.
Then some of the liquid will vaporize. Then some of the ...
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Have guided diffusion models been applied in the chemistry informatics domain yet for molecule prediction/generation?
Guided diffusion models have been a big deal in machine learning recently. Are you aware of any literature (i.e. preprints or peer-reviewed publications) that have applied guided diffusion models in ...
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Has tellurium(II) iodide been properly characterized ever?
According to Wikipedia, tellurium tetraiodide decomposes on heating:
$$\ce{TeI4 ->[\Delta] TeI2 + I2}$$
However, the reaction is somewhat wrong as according to this 2008 paper:
Solid tellurium ...
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What is the least dense liquid under normal conditions?
What is the least dense liquid under normal conditions, room temperature, one atmosphere of pressure, doesn't combust upon contact with air, also wouldn't kill a human just for being in the same room ...
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Thermal oxidation of gold(I) sulfide
As far as I know the chemistry of $\ce{Ag}$ and $\ce{Au}$ are almost the same; because $\ce{Ag}$ belongs to the 4d series and $\ce{Au}$ belongs to the 5d series, we know the size of 4d and 5d are ...
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Bond angles of dichlorine and dibromine monoxides
Most online sources suggest that the bond angle of $\ce{OBr2}$ is greater than the one of $\ce{OCl2}.$ It is explained by the electronegativity difference and electron repulsion within the VSEPR ...
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What solvent dissolves calcium nitrate but not ammonium nitrate?
I am experimenting with a precipitation reaction between ammonium sulfate solution and calcium nitrate. Calcium sulfate precipitates and can be filtered out easily.
I am wondering if there's a way I ...
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Can all 20 H atoms of pentagonal dodecahedrane be substituted with high yield and a wide range of substituents? What limits full substitution?
I first came across dodecahedrane in comments below What dodecahedral molecule is Linus Pauling likely holding in this photograph? Does it have 40 carbon atoms?
Wikipedia's Dodecahedrane; Derivatives; ...
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How can benzaldehyde have a pKa of 14.9?
There are numerous websites out there which claim that the pKa of benzaldehyde – C6H5CHO – is 14.90. (Just do a Google search for benzaldehyde pka to see what I ...
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Ellingham diagram/graph for tungsten
I've recently come across one of the methods to form tungsten carbide($\ce{WC}$) from wolframite ($\ce{(Fe,Mn)WO4}$) by using carbothermic reduction which was supposedly one of the first methods for ...
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Feynman books analogous in chemistry [closed]
Is there a analogous to feynman lectures in physics but for chemistry? Like a book ir series of books that covers all the basics?
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Production of ʟ-glucose
What chain(s) of reactions are used to produce ʟ-glucose? I did a search on Google Scholar, but to my surprise nothing came up. My guess would be that the synthesis starts from ᴅ-glucose for which ...
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Reliable data describing acidity of 2,4,6-trinitrobenzenesulfonic acid
I wonder what is the $\mathrm{p}K_\mathrm{a}$ or the value of Hammett's $H_0$ function of 2,4,6-trinitrobenzenesulfonic acid? PubChem gives $\mathrm{p}K_\mathrm{a} = 0.13,$ but doesn't specify the ...
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Newer ionic radii data than Shannon's 1976 compilation?
Shannon, R. D., 1976, Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides: Acta Crystallographica Section A, v. 32, p. 751–767. DOI: 10.1107/...
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Does the largest known cycloalkane contain 288 carbon atoms?
If you Google "largest known cycloalkane", you will find this result:
For context, there has been discussions on "largest known alkane":
Largest alkane having a given alkane as ...
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Caffeine molecule representation and orientation
Almost all the representations of the caffeine molecule that I've come across have the two rings drawn next to each other on the horizontal axis.
Any particular reason for this?
Would it be sacrilege ...
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Resources for learning Chemistry
Based on various other Stack exchange site (Mandarin Chinese, Russian and German), we adapt this project here for chemistry, since it's a great idea to have all kinds of resources in one place.
This ...
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How can I calculate the charge distribution of a water molecule?
I would like to obtain the 3D charge density of a water molecule for plotting purposes (i.e. not necessarily super-accurate). I know this is a tough problem, but I'd like to give it a try. Since I'm ...
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Mapping of half-life decay for all elements/isotopes
Is there an open resource that helps illustrate all paths of decay for all isotopes (e.g. $\ce{^{99}Mo}$ decaying to $\ce{^\mathrm{99m}Tc})?$ I know the result state/transition map would be massive, ...
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IUPAC name of benzoyl chloride
I came up with two possible names: benzoyl chloride and benzene carbonyl chloride. I believe both names are correct.
Wikipedia says that the preferred IUPAC name is benzoyl chloride:
Can someone ...
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Reason for the formation of azeotropes
Why is it that some liquid mixtures (that exhibit positive/negative deviation from Raoult's law) form azeotropic mixtures at certain compositions? What is the physical reason behind this; are there ...
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Interpretation of azeotropes from statistical mechanics derivation
In an earlier posted question titled Reason for the formation of azeotropes, @porphyrin presented an elegant derivation from statistical mechanics to interpret partial pressures for the two components ...
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What is double titration?
I an currently studying acid-base titrations. There is a concept of double titration. Can someone provide me an idea on what actually it is? Also what resources can I refer to?
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Where can i find accurate bond angles?
I am trying to find places where I can have accurate bond angles of certain molecules such as $\ce{F2Se}$, $\ce{Cl2S}$, or even $\ce{S2Se}. I have looked everywhere and have found only 3 sources that ...
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Where to find the ChEMBL21 database in CSV format?
I come from an artificial intelligence (AI) background (and not from chemistry).
However, my Ph.D. thesis is about Deep Reinforcement Learning for drug design.
From one of the most famous papers in ...
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What is Nesbet's theorem?
In a talk by Frank Neese there was a slide with title "Nesbet's theorem" and an equation indicating something like "if your wavefunction has the double excitation amplitudes correct, then you can get ...
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What is the chemical composition of Ferrous Ferrocyanide?
To this day, iron-cyanide complexes confuses me. So, I want to settle this once and for all. After scavenging the internet, I gathered the following result:
$$
\ce{Ferr}
\color{blue}{\ce{ous}}~\ce{...
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References for recommendation guidline values (cyclic hydrocarbons and i-alcylated hydrocarbons)
I am studying a measurement protocol of VOC emissions of a rubber gym flooring product and stumbled over some substances I didn't found any guideline values such that below this value it seems to be ...
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Electrode potential of Br2/HBr half cell
I am wondering if it is possible to find the electrode potential of such a half cell:
$$\ce{Br2 (l) + 2 e- <=> 2Br-(g)}$$
The standard electrode potential is for $\ce{Br-(aq)}.$ However, is it ...
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What is "activated red phosphorus"?
[WP = white phosphorus ; RP = red phosphorus ; ARP = activated red phosphorus]
A YT channel, Extraction & Ire has a video from two years ago (2018) on converting WP to RP by keeping the former in ...
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Does mercury(II) cyanate exist?
Recently, I have answered a question "Comparing explosive properties of mercury(II) cyanate and mercury(II) fulminate" where stability of cyanate vs fulminate was discussed. While I was ...
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Which plastic type is used inside dishwashers?
We have a drinking bottle made partly from polypropylene that wraps when washed in a dishwasher. We would like to change the plastic type so that it can withstand in dishwasher.
I know for a fact ...
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What are all the steps on the organic chemistry diagram called The Boat?
When I learnt A-level chemistry, I was told to use a diagram the teacher called The Boat.
It was a diagram illustrating all the chemical reactions that you can do to simple organic compounds. For ...
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Anomaly in Faraday's constant measurements
I was reading someone's biography, where the writer stated his early interest in Faraday's constant measurements (this is set six decades ago). My understanding was that Faraday constant is a true ...
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How is the vibration of multiple atoms treated in vibrational spectroscopy?
Most of the advanced undergraduate textbooks on physical chemistry/ instrumental analysis show the case of a diatomic harmonic oscillator and derive formulae for predicting the frequencies. The ...
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Nucleophilicity of sterically hindered enolates
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Here $\ce{KH}$ obviously acts as a base, and forms the enolate from the ketone, which subsequently act as nucleophiles causing an SN2 reaction on the $\ce{CH3I}$. When this ...
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Reference request: book that covers an overview of useful materials
I was wondering if there is a book that has a broad coverage of inorganic materials, like concrete, glass, and steel.
Ideally the book would go into how each material is manufactured and some of the ...
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Do CHF3 and acetone form a hydrogen bond?
I haven't been able to find a reference confirming that fluoroform forms hydrogen bonds with acetone. Do they?
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Fluorescence quenching by palladium(II) vs. platinum(II) complexes
Why do we observe much stronger (in most cases complete) fluorescence quenching by $\ce{Pd^2+}$ than $\ce{Pt^2+}?$ I work with complexes of both metals and there is no real 100% explanation I can find ...
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Approximate magnetic susceptibility of these liquid propellants?
This question asks if the comparatively large paramagnetic susceptibility of liquid oxygen (LOX) is considered when designing rocket tank and engine systems. This comment suggests fuels such as RP-1 (...