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PubChem 3D has limits on the number of 'rotatable bonds' I recently answered a related question about PubChem 3D: Beyond the limits of MMFF94 and MMFF94s themselves, PubChem3D had several limits indicated in the accompanying manuscript: Bolton et. al. "PubChem3D: a new resource for scientists" J Cheminf. (2011) v. 3, art. 32) Not too large (with ≤...


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This is a class of carbocation 1,2-rearrangement reactions, and historically named Wagner–Meerwein rearrangement after two chemists who discovered the reaction (see following diagram): Although it can be explained considering as an rearrangement of a classical carbocation, there are a tremendous amount of work has been done considering 2-norbornene cation ...


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Oil production areas use a personal badge; lead acetate , it darkens if H2S is present ( Draeger was a brand for detection equipment).


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On the premises of an oil refinery, if you are not staying completely indoors, everybody gets one of these: They give you an alarm if the H2S concentration goes above a few ppms, and the sensor inside typically can (quantitatively) measure up to one or two hundred ppm before it goes into saturation.


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There are simple test tubes available for the measurement of $\ce{H2S}$ and similar compounds in air. For example this one by Dräger (no affiliation), which uses oxidation by iodine. $$\ce{H2S + I2 -> 2 HI + S2}$$ The (discoloration of the) brown color of the absorbed iodine serves as indicator. In order to get a quantitative result for the concentration ...


3

Chemical surfactants or dispersants are useful for cleaning up oil spills. They break up the oil slick and allow the oil to become dispersed in the water, so that naturally occurring bacteria can break down and oxidize the hydrocarbons in the oil. Dispersants are typically designed to be water-soluble at one end and oily at the other end--basically soaps or ...


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The paper by Order and Lindwall [1] agrees with you that the R-T reaction gives indole-3-carboxaldehyde. Since its isolation in 1903 by Hopkins and Cole (1), 3-indole aldehyde has been investigated very little. It was first prepared by Ellinger (2) from indole through the use of the Reimer-Tiemann reaction. This method was improved on later by Boyd and ...


3

Now a days, sulfonephthaleins can be prepared by reaction of readily available saccharin and the desired plenol compound (Ref.1 & Ref.2). In this method, active reagent, sulfobenzoic anhydride will be prepared in situ as depicted in following diagram: In this method, it's described the preparation of phenolsulfonephthalein (Phenol Red). If you use ...


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Avoid aluminum alloys when working with vinegar solutions! With time, the pH effect of acetic acid can penetrate the protective oxide coating. The exposed Al will even react with water: 2 Al (s) + 6 H2O (l) --> 2 Al(OH)3 + 3 H2 (g) and with the presence of alloy metals, galvanic corrosion (especially if the 'dirt' is rich in salts that can serve as a good ...


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Hyperconjugation is seen when there is a vacant p orbitals to where Alpha hydrogens can relocate their electrons.Conjugate base of ethanol does not have any vacant p orbitals. So hyperconjugation doesn't play any role in stabilization of conjugate base. The stability of alkoxide ions in solution is determined by how much they get solvated in aqueous ...


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This is an answer to a question of mine, which I posted a few days ago, Deprotonated form of phenolphthalein. I found this paper (it's in Japanese, but the relevant things are legible) https://www.jstage.jst.go.jp/article/yakushi1947/117/10-11/117_10-11_764/_pdf, which says that phenolphthalein has 2 pKas, pKa1 = 9.05 and pKa2 = 9.50. It also says that the ...


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A copper mirror can be obtained by heating two or three grams of dry copper formate $\ce{Cu(HCOO)2}$ in a test tube with a Bunsen burner. For some reason, the copper atoms are deposited on the inner surface of the test tube. Try it! It is easy to do!


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A copper mirror can be formed, for example by reaction between $\ce{Cu(NH3)4^{2+}}$ and hydrazine in basic solution. That being said, copper in general forms mirrors less easily than silver because copper is harder to reduce to the metal. This data page gives a standard reduction potential of about 0.34 V for reducing copper(II) to the metal but about 0.80 ...


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In the case of o-nitrophenol, the acidic hydrogen is hydrogen-bonded to the nitro group's oxygen atom, making it less acidic. In the case of catechol, one acidic hydrogen is hydrogen-bonded to the adjacent OH group's oxygen atom, but the other, more acidic hydrogen is not hydrogen bonded. This hydrogen is more acidic than that of hydroquinone. The resulting ...


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Your suggestion of resulting corresponding hydrazone by the reaction between acrolein and hydrazine is correct. It is normal hydrazine-hydrozone reaction you perform in idetifocation of aldehyde and ketone carbonyl groups. Usually, E-isomer is preferred (Ref.1). E- to Z-isomerization can be occurred in presence of trace amount of acid (Ref.1). I expect that ...


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I think the only real option for this is a clear plastic sheet that's had a chemical resistant thin film applied to the faces. One commercially available example is Makrolon AR2, it's polycarbonate with some proprietary coating that's listed as having >24hrs resistance to acetone and a few other chemicals.


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$\boxed{\textbf{d}}$ is correct. It is the standard IUPAC name. However, "2,4,6-trimethyl cyclohexanone" will often be understood as 2,4,6-trimethylcyclohexanone, similar to how, in theory, neopentane, 2,2-methylpropane and 1,1,1,1-methylmethane are all equivalent.


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