Search results
Results From The WOW.Com Content Network
As such, all compounds on the TLC plate move higher up the plate in polar solvent mixtures. [citation needed] "Strong" solvents move compounds higher up the plate, whereas "weak" solvents move them less. [11] If the stationary phase is non-polar, like C18-functionalized silica plates, it is called reverse-phase TLC. In this case, non-polar ...
is an alkaline solution of potassium permanganate; used in organic chemistry as a qualitative test for the presence of unsaturation, such as double bonds; N-Bromosuccinimide: used in radical substitution and electrophilic addition reactions in organic chemistry. Also acts as a mild oxidizer to oxidize benzylic or allylic alcohols.
Chromatography – a physical method of separation that distributes components to separate between two phases, one stationary (stationary phase), the other (the mobile phase) moving in a definite direction. Eluent (sometimes spelled eluant) – the solvent or solvent fixure used in elution chromatography and is synonymous with mobile phase. [11]
Around 90% of all pharmaceutical separations are performed on normal phase silica gel; however, other stationary phases such as alumina can be used for samples with dissociating compounds and cellulose for ionic compounds. [4] The reverse-phase HPTLC method (similar methodology to reverse-phase TLC) is used for compounds with high polarity.
Triphenylphosphine oxide can be difficult to remove from reaction mixtures by means of chromatography. It is poorly soluble in hexane and cold diethyl ether. Trituration or chromatography of crude products with these solvents often leads to a good separation of triphenylphosphine oxide.
From left to right solutions of 0.1 M HCl, 3 buffer solutions of pH 3.78, 3 of pH 4.00, 3 of pH 4.62 and NaOH 0.1 M after adding different amounts of bromocresol green (more in darker solutions) In aqueous solution , bromocresol green will ionize to give the monoanionic form (yellow), that further deprotonates at higher pH to give the dianionic ...
Chromatography employs continuous adsorption and desorption on a packed bed of a solid to purify multiple components of a single feed stream. In a laboratory setting, mixture of dissolved materials are typically fed using a solvent into a column packed with an appropriate adsorbent, and due to different affinities for solvent (moving phase ...
Thin layer chromatography (TLC) is a quick alternative to more complex chromatography methods. TLC can be used to analyze inks and dyes by extracting the individual components. [18] This can be used to investigate notes or fibers left at the scene since each company's product is slightly different and those differences can be seen with TLC.