# Tag Info

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Whether or not the ice cube will adhere to something is dependent on the temperature of the ice, the state of the surface of the ice, and the moisture content of the material. The temperature of an ice cube can range from the freezing point of water ($0\ \mathrm{^\circ C}$) to well below this temperature. Typically most materials have a small degree of ...

23

You could imagine stirring the sugar enough for the water molecules to be uniformly distributed throughout - it would then be homogeneous. However, even then, to refer to the mixture as a solution of water in sugar is unhelpful, not least because referring to a slightly damp solid as a solution will only confuse. A definition needs to be useful, as well ...

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To directly address where the phrase comes from: Water is called the "universal solvent" because it dissolves more substances than any other liquid. -USGS What are ideal qualities of solvent? The strength of a solvent can be attributed to the strength of its intermolecular forces like london forces, dipole-dipole forces, ion-induced dipole, and hydrogen ...

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TL;DR: Water is incredibly easy to get and work with. In full Water is a good solvent for polar compounds[citation needed], and the reasons for this are laid out pretty well by John Snow, but that's not really what makes it the universal solvent. Instead, a series of other, incidental properties makes it a popular choice: Availability There's a lot of ...

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There is no list per se, but there is certainly a process to determine appropriate solvents for a given reaction. For the specific reaction you mention, here are some criteria you would consider to select a solvent: Because this is an oxidation reaction, choose a solvent that cannot be oxidized, known as an aprotic solvent. The solvent needs to dissolve ...

17

Both answers are right. In the IUPAC Gold Book it states A liquid or solid phase containing more than one substance, when for convenience one (or more) substance, which is called the solvent, is treated differently from the other substances, which are called solutes. So either way can be used, but it is usually more conventional to call the ...

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Just to provide an alternative answer: Consider a solvent miscibility table like the one linked. What is the least miscibile solvent? Water! Water is the worst solvent. Water is immiscible with 17 out of 30 of the other listed solvents. There are 6 solvents in the table which are miscible with all the other solvents: ethanol, acetone, tetrahydrofuran, n-...

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The short answer is: yes, this is possible. Unfortunately, solubility is a fairly complex phenomenon to explain simply. Let's start with some examples where solubility is higher in a binary mixture than either solvent alone. For a solid-liquid-liquid example: phenanthrene-cyclohexane-diiodomethane.[1] For a liquid-liquid-liquid example like the one you were ...

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When most people think of the term solvent, a liquid medium comes to mind; however, in the technical sense of the definition, this does not have to be the case. Here is the definition of a solution present in the IUPAC gold book: A liquid or solid phase containing more than one substance, when for convenience one (or more) substance, which is called the ...

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Because $\ce{CO_2}$ isn't exactly what's being dissolved. When it encounters water, it immediately encounters the following potential reaction: $$\ce{CO2~(g) + H2O~(l) <=> H2CO3~(aq)}$$ Carbon dioxide is non polar, yes, but carbonic acid readily dissolves (and dissociates, but I didn't care to show that) in water. The sound we hear is because when ...

13

There is a minimal volume you need to fill into the NMR tube to be able to get a good shim, this is around 500 microliters with regular 5mm tubes. Not using a solvent would require a lot more of your actual sample just to fill the tube. In many cases you might not even have enough of your product to fill an NMR tube. The solvent does have some effect on the ...

13

I did organic chemistry in the lab for 9 years, and never once was there such a list. There are general rules for protic vs. aprotic and polar vs. non-polar, but a lot of times, when a reaction is published, the authors did a study of different kind of solvents and selected the "best" based on yield, reaction rate, ease of purification, or selectivity.

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If you consider YANR (your average name reaction), the scientists who published said YANR will typically have done a set of screenings, including a ‘solvent screen’. That means, they will have run said reaction in a number of different common laboratory solvents and compared the yields. The table will then look something like this (disclaimer: all values in ...

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The key point is driving the equilibrium where you want it. You could do it by relative reaction rates. The Finkelstein reaction, however, uses a better method: precipitation of one of the products. Acetone is specifically chosen because sodium chloride, bromide and fluoride are insoluble in it while sodium iodide is soluble. So the equation becomes: $$\ce{... 11 Boiling depends on certain properties of a solvent: Tendency to form an emulsion of bubbles due to low surface tension and separation of solvent phases, as in soap bubbles. Try boiling some dish-washing detergent in water. Tendency to superheat, i.e. to go well above the boiling point and then to suddenly form bubbles, which is more pronounced at lower ... 10 Cyclodextrins, which comprise a class of cyclic carbohydrates, use their properties of being hydrophobic within their ring(s), yet hydrophilic outside. Alcohol can be put inside these rings. Then, the entire molecule is still capable of dissolving in water, releasing the encapsulated alcohol molecules. (src) This popsci link has one way of making edible ... 10 It's worth noting some of the history behind the term "universal solvent," and why it is used even though water isn't truly universal or even necessarily the most versatile solvent available. Before chemistry existed, and for that matter before science existed as the practice we would recognize today, alchemy was an important protoscience. A number of ... 10 Just to add some clarity to some already acceptable answers by others.... For running solution (liquid) state NMR, a solvent is not necessary. There are a number of applications where dilution with a solvent is unwarranted and counterproductive. So, why use a solvent for running liquid state NMR? The main reason a solvent is used is to improve the ... 9 By far the safest solution is to physically abrade the surface until you have worn away everything that isn't copper. This is slow and requires some sort of grinding agent but has the upside that you are not likely to injure yourself. There is a chemical solution that will work but it requires access to some dangerous chemicals and is extremely hazardous ... 8 The nature of the substrate (in particular the degree of substitution of the α-carbon) is of principal importance in determining which mechanism predominates. Generally, \mathrm{S_N1} and \mathrm{E1} are both less common than \mathrm{S_N2} and \mathrm{E2}, partially as a consequence of their first-order kinetics and the stability constraints imposed ... 8 Many of the chemicals used in metal plating are extremely poisonous (cyanide), cause severe allergies (Ni), and are carcinogenic (Cr(VI)). I'd consider it as extremely unprofessional (besides violating many laws and regulations), to re-use anything that has been in contact with these materials for any purpose that requires a 'clean' container, regardless of ... 8 The mixture of dry ice and acetone is used outside your reaction vessel to keep the vessel cool just as a water bath is sometimes used to provide uniform heat to a reaction vessel. The only role is to provide a uniformly cool environment for the reaction vessel. Acetone isn't the only choice here and isn't essential (anything still liquid at the temperature ... 8 Ethanol and methanol dissociate into ions, just as water does. For water:$$\ce{2 H2O <=> H3O+ + OH-}$$For an alcohol \ce{ROH}:$$\ce{2 ROH <=> ROH2+ + ^-OR} For water the self-ionization constant is $K_\mathrm{w} \approx 10^{-14}$. For ethanol or methanol, I was unable to find data on the self-ionization constant, which is essentially ...

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The solvent appears not only to have removed paint on the keys but also to have caused solvent crazing in the plastic itself. Regrettably, there is probably not much that can be done to actually remove the crazing, which may have penetrated too deeply to remove by buffing, but you might be able to hide it with a substance such as an oil that has the same ...

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Usually I avoid pipetting diethyl ether because it can be a bit annoying, but recently I've realized there is a very simple technique which markedly increases ease of transfer (though admittedly I've been using it mostly for DCM). All you have to do is saturate the interior of the pipette with the vapour of the low-boiling solvent before performing the ...

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In the presence of UV light, chloroform can be oxidized by atmospheric oxygen to phosgene ($\ce{COCl2}$), a toxic gas. The dark colored glass blocks UV light so that phosgene is not produced.

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The question is flawed since we do not know whether the resulting mixture consists of a single phase or not (I guess that there are two phases). Moreover, the definition solute + solvent = solution; between the solute and the solvent, the solvent is one present in larger quantities and is in the same phase/state of matter as the solution seems to be a ...

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Benzene is a good solvent for many organic compounds, the term good solvent to me does not mean a nice solvent with a good all round profile. To me the perfect solvent would be non toxic, not flammable but combustable, very resistant to radiation, inert to nitric acid, be easy to distill, be cheap and easy to obtain. It would also have to be able to ...

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