Raoul Kessels
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How to capture the gas produced by combusting alcohols
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If you look at the overall reaction, there is actually no gas produced, but there is a consumption of gas: $\ce{CH3(CH2)_n-OH + \frac{3}{2} (n + 1)O2 -> (n + 1)CO2 +(n + 2)H2O}$ So 1.5 mol of ...

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How do you get contents of large flask into a smaller separatory funnel?
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You should proceed as follows: Charge the funnel with the mixture until it is almost full. Let the content settle. Separate the lower phase. Separate the upper phase. Repeat until you have ...

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Solubility of Iodine in Some Organic Solvents
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Iodine forms charge transfer complexes, most notably with starch. In these complexes, a fraction of the electronic charge is transferred to the other molecule. The formation of these complexes ...

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Regarding acid-base reactions, how does one know when a hydrophobic base substance is fully protonated?
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Yes, that is correct. As you add HCl, the pH will remain more or less constant at around 5, since in solution there is a salt of a strong acid and a weak base. Then when all the base has been ...

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Why is cooking not potentially lethal?
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During cooking many harmful compounds are formed, but they are not immediately lethal. However, long exposure to the same harmful compounds can be lethal in the end. Therefore it is important to ...

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Concentration of excess reactant
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A very typical situation in organic chemistry is the following: $\ce{A -> undisired products}$ $\ce{A + B -> target product}$ Here it is easy to see that increasing the concentration of $\ce{B}...

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Is every compound that has a H-bond donating group soluble in water?
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Definitely not. For instance, palmitic acid with a pK$_\mathrm{a}$ of 4.75 has a water solubility of only 0.04 mg/L. A general rule of thumb is that every oxygen can solubilize four carbon atoms ...

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Benefits of a Buchner funnel w/ a fritted disc instead of Quantitative Filter Paper Circles
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Buchner + filter paper cons: The filtering surface is not uniform. It filters only where the holes are, so most of the surface is not working. Some solid can slip between the paper and the filter. ...

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How good is aromaticity at stabilization?
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The situation in S and P is very similar. Essentially you have a negative charge $\alpha$ to two double bonds which will delocalize these charges. In the case of cyclopentadiene, this will be ...

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Biological contamination from ground
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The point is not how large the possibility is. There is a possibility that the flask has been contaminated, so you should have taken a new flask. I suppose you did not have a spare one with you. ...

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HPLC method for salicylic acid
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Reverse phase is the standard in HPLC so, if you can use reverse phase do not complicate matters. Normal phase usually gives more problems than reverse phase and the stationary phases degrade faster. ...

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Why are acetylene and air commonly used for AAS?
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Because it gives a very high temperature: 2200-2400 $^\circ$C. This is due to its high heat of combustion, around 1300 kJ/ mol. If still higher temperatures are required, as for Al, Si, Ti, etc., a ...

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Electrochemical manufacturing of small metal components
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Nice idea, but difficult to do. The copper cations must continuously enter the "mold" electrode to grow there, but they must not be able to grow outside. If there are holes in the "mold" the ...

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Chemical tests given by glucose (biomolecule)
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This are two different types of reactions. Tollens is a redox reaction in which silver is reduced and glucose is oxidized. This reaction depends on the redox potential of glucose only. Schiff and ...

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Effect of rain on water and soil samples contaminated by petroleum
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It has much sense since the rain will modify the concentrations of both the heavy metals and the petroleum. The initial quantities will be redistributed. One part will penetrate deeper in the ground, ...

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Acid in Imine Formation
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You can use any acid, since it will be immediately neutralized by the amine. The p$K_a$ of $\ce{H2SO4}$ is $-9$ while that of TosOH is $-6.5$, but both will form $\ce{EtNH3^+}$ which has a p$K_a$ ...

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Is it possible to calculate the concentration percentage using chromatography paper?
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Yes, it can be done. I have done it on silica plates to compare the content of a natural product in different samples of plants. It is , obviously, better to use HPLC, but in that case the sample ...

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How long does it take to saturate H2O with O3
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The solubility of ozone in water as per one website is: First thing is to establish which curve you need. In 1 m$^3$ gas you have 70 L ozone: $\frac{70\ L\ \ce{O3}}{1\ m^3}\frac{1\ mol}{0.082\cdot ...

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Do acids react with neutral salts?
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Neutralization is a reaction between acid and base which results in the formation of a salt and water. When you have any ionic compound and dissolve it into water, dissociation occurs. This means that ...

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Does deuterium exhibit hydrogen bonding?
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In short: Chemistry is about the last shell of electrons in the atoms. Nuclear differences are in the field of Physics. Deuterium is only a nuclear isotope of hydrogen, so no fundamental ...

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Synthesis of Benzaldehyde and Aniline Schiff Bases
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The reaction needs acid catalysis but ethanol is fine as solvent. There will always be some starting materials left, but since the product is a solid and the reagents are liquid, the best (and ...

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How to dissolve PLA (polylactic acid)?
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When I started 3D printing I did some trials to dissolve PLA. I tried acetone, caustic and some other solvent. The only one that worked very well at room temperature was methylamine in water. ...

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If stirring negatively affects crystal purity, why is it so?
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Stirring during crystallization is positive for the purity of the crystals. The explanation is that with stirring, your liquid phase will be homogeneous. Then, there are some other details. Many ...

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How does the equilibrium shift when concentration of reactant and product are increased simulatenously
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In an equilibrium, the equilibrium constant remains the same. When you change the concentration of some component, the whole system shifts to new concentrations to maintain this constant. When one ...

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What is the difference, if there is, between this two distillation methods?
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There is no fundamental difference between the two methods. In both cases steam is formed and it is passed through the plant material. The intention is to extract the non volatile water insoluble ...

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What are the differences between D and L glucopyranose?
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They are mirror images of one another and therefore their chemical and physical properties are the same, except for the deflection of polarized light, which will be in opposite directions. Mirror ...

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Percentage of trans-stilbene traces in cis-stilbene H NMR
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You have to focus on the $\ce{^1H}$ of the double bond. They are singlets because both molecules are completely symmetrical. As per the tables, the chemical shift of the cis isomer is $5.25+1.38-0....

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what is the product of this reaction and mechanism?
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Yes, the oxigen is protonated, water enters, methanol leaves and another $\ce{H^+}$ is released. Then the oxigen of the other $\ce{CH3O}$ group is protonated, the keto group is formed while the ...

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When there's a photoelectric effect, do the electrons leave altogether or leave one by one?
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Only electrons that are hit by a photon with the appropriate wavelength will be moved. So that means that they are leaving one by one. This can however ocurr at several places at a time so that means ...

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Separation of solvent from residue of material.
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Distillation is the way to go. Especially if you have to do it on industrial scale (if we have understood well, you have 2000 L to process). Normally it yields recovered solvent with low level of ...

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