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1

In addition to all the qualities @Karl stated (harmless, edible, overspray decomposes, etc.), such a coating would also need to stretch as the produce grows. Such a protective covering might even obviate the need for pesticides, if it were to be created. That said, there are edible wax and protein coatings to preserve produce after it's picked. ...


4

While I can't find specific justification for the surface, the first competition involved both gold and silver "racetracks." Drivers gear up for world’s first nanocar race How to build and race a fast nanocar The competition involves propulsion and imaging using STM so the substrate must be conductive. Gold (and silver to a lesser degree) is particularly ...


17

I think the term describing the initial process of separation of the solid phase (dust particles) from the gas phase via bubbling is a wet scrubbing process. On an industrial scale, it's more efficient to spray liquid phase, whereas on a laboratory scale bubbling in a compact glass gas scrubber or a gas washing bottle is more convenient. In order to ...


0

The equilibrium constant depends on temperature, the only thing it depends on. For an exothermic reaction the equilibrium constant will decrease ie shift towards the reactants side Also consider kinetics as described above


3

There are two separate effects we need to consider here: thermodynamic and kinetic. Let's assume you are only providing the energy thermally. So providing more energy means increasing the temperature (T). Thermodynamically, if a reaction is exothermic, and you increase T, the reaction becomes less favorable (assuming it stays exothermic over that ...


1

To reason about the kinect reaction you must consider the mechanism of the reaction. Honestly I can't say much about this reaction specificaly since the oxidation mechanism by KMnO4 is considerably complex and not much studied probably until graduate courses. I can say, however, that you can't reason about the reaction kinectics under the consideration of ...


3

Procedure from the paper by Xie et al. [1] (Powder XRD didn't reveal any other impurity phases in the bulk samples): Synthesis of $\ce{CH3NH3PbI3}$. The as-prepared $\ce{CH3NH3I}$ and $\ce{PbI2}$ (Sigma-Aldrich, 5N) were mixed in stoichiometric ratio and dissolved in γ-butyrolactone (Sigma-Aldrich), and then a 40wt% solution was formed. The solvent of as-...


5

Note: this is a preliminary description, which I think answers the question, but disagrees in one detail (see asterisk). Tin(IV) iodide is completely hydrolyzed by water [1, p. 120] to colorless hexahydroxostannic acid: $$\ce{SnI4 + 6 H2O <=> H2[Sn(OH)6] + 4 HI}$$ Hydrogen peroxide can not oxidize $\ce{Sn^4+}$ further (in fact, hexahydroxostannate(...


1

If we consider this from a diffusion perspective, your concept might not be as effective as you might think. Graham's Law of diffusion and effusion of gases states that the rate of diffusion for a gas is inversely proportional to its molar mass ($M$): $$rate_\text{gas A} \propto \frac{1}{\sqrt{M_\text{gas A}}}$$ So, if we want to compare the rate of ...


-1

You don't get a precipitate if you add coppper(II) sulfate to hot salicylic acid. It becomes a clear dark green liquid. I assume the low pH because of the addition of the sulfate ion causes the formation of an acidic complex. I added some bicarb and the copper salicylate formed a light green powder. I added enough till it stopped effervescing as I don't have ...


-2

The base should be in the burette, and the acid in the flask. With this technique, the point of equivalence is obtained with a rather high degree of accuracy.


2

The bubbles are still hydrogen. Transition metal salts are generally much weaker acids than whatever you put your magnesium ribbon into for your hydrogen control. So you get less gas for the candle flame to react with when you use the transition metal salt, which I am sure you saw. That the decreased amount of gas still popped, which is basically a low-...


3

A plasma discharge certainly can transfer charge. Plasma guns are commonly used to reduce static charge, e.g. when pulling plastic wrap from a roll or for cleaning dust from vinyl discs. Small ones are available from about US$100 and larger plasma guns for more. Or you could make your own plasma gun, using a piezoelectric generator from a US$1 lighter. ...


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