What are the similarities & differences....
Are there any essential features that one should keep in mind about them?? any specific uses etc???
2007-02-16 20:41:13 · 2 answers · asked by Kay :) 3 in Science & Mathematics ➔ Chemistry
Some similarities include both techniques are used to physically separate chemical compounds. They both have a solid stationary phase and a liquid mobile phase to do this separation. Also they both can be used to help identify compounds (qualitative analysis).
The differences are many. TLC allows unknowns and known standards to be run at the same time (it is a 2-dimensional technique). It is also highly limited in the amount of compound that can be separated. This makes the thin layer method ideal of screening (like drug tests).
Columns, on the other-hand, can be very large and used for product separation. This allows very impure reaction mixtures to be separated into products and by-products and unreacted starting material very easily.
Some versions of column chromatography can also use pumps to move the mobile phase under pressure (called HPLC). This method can be easily automated, allowing for a very large number of samples to be analyzed with minimum human labor.
Column chromatography also include other methods of sepatation such as chiral, ion exchange, size exclusion and affinity techniques. These are rarely done with TLC.
2007-02-16 21:24:15 · answer #1 · answered by Richard 7 · 10⤊ 0⤋
Thin layer chromatography(TLC) is a technique to find the dyes in a specimen.It is used in forensics to identify a certain piece of clothing be cause paint or dyes differ in chemical composition, even the ones that are supposed to be completely similar. This usually does narrow the range to a much smaller amount.
2016-05-23 21:59:37 · answer #2 · answered by Anonymous · 0⤊ 0⤋