2007-02-27 05:05:17 · 2 answers · asked by Charlotte R 1 in Science & Mathematics ➔ Chemistry
They are usually pretty accurate. While TLC is used to test for purity, the Rf value does no such thing. It should only be used for Identity of a compound. For example, if you have an unknown, you can use the Rf value and compare it to the known Rf value of some known compound to determine the identity. To make sure they are accurate you should mark the solvent front immediately after the removal of the plate. If you don't, then the solvent will evaporate and you will not be able to see the front again.
2007-02-27 05:46:50 · answer #1 · answered by BeC 4 · 0⤊ 0⤋
make sure to mark where the spot starts and where the solvent front ends. tlc is used as a judge of purity of a product - ie is there only 1 or more than one. make sure plate doesn't fall over into the solvent as it will streak more than normal.
liquid chromatography can do much of the same things, and more accurately, but it is MUCH more expensive.
2007-02-27 05:20:19 · answer #2 · answered by shiara_blade 6 · 0⤊ 0⤋