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There are many different ways of using chromatography. You may use it as an analytical tool, like in your figure. But you may also use it for preparatory goals. For example if you have a liquid containing some impurity that you know is adsorbed on silica or alumina, you may use a long and broad glass tube, put it in a vertical position and fill it with ...


Generally, all chromatography is done on silica gel. It's the exact same procedure for TLC (thin layer chromatography), except that instead of paper you have a thin layer of glass covered with silica. What can be done in that case is scraping the spots, then extracting the product with organic solvents and filtration. There exists plates made for this, which ...


$\ce{CaCO3}$ is not soluble in water. Both $\ce{KCl}$ and $\ce{NH4Cl}$ are soluble in water. When heated $\ce{NH4Cl}$ sublimes at 335 °C. At this temperature, $\ce{CaCO3}$ and $\ce{KCl}$ are not modified. $\ce{CaCO3}$ is decomposed in $\ce{CaO}$ and $\ce{CO2}$ at 825 °C.


The standard method for ketalization is illustrated in the reaction of cyclohexanone 1 with ethylene glycol to form the ketal 2. The reaction is reversible which requires irreversible removal of water shifting the reaction to the right. In this reaction the toluene/water azeotrope may be separated by a Dean-Stark trap. Because of an unfavorable equilibrium, ...


You could use electrolysis with a mercury cathode, taking advantage of its huge hydrogen over potential that makes sodium reduction kinetically favored. The sodium is amalgamated into the mercury. Now all you need is to separate the sodium. Unfortunately, just evaporating the mercury would (1) probably get you into the news headlines when the toxic ...


You cannot separate sodium from a solution of sodium iodide NaI. If you try to do it by electrolysis, the sodium produced at the cathode will immediately react with water with the following reaction : $$\ce{2 Na + 2 H2O -> 2 NaOH + H2O}$$ and you will just obtain some sodium hydroxide NaOH in your sodium iodide solution

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