Question: How Do You Read TLC Plate Results?

What is the principle of TLC?

What is the principle of TLC.

TCL is based on the principle of separation through adsorption type.

The separation relies on the relative empathy of compounds towards the mobile phase and stationary phase..

What is TLC used for?

Thin layer chromatography, or TLC, is a method for analyzing mixtures by separating the compounds in the mixture. TLC can be used to help determine the number of components in a mixture, the identity of compounds, and the purity of a compound.

What happens if the spots are made too small when preparing a TLC plate for development?

2What happens if the spots are made too small when preparing a TLC plate for development? -If the spots are made too small when preparing a TLC plate for development, it will be very difficult to observe the results or there will be no spots at the end of the process.

What does a TLC plate tell you?

Thin Layer Chromatography (TLC) is a separation technique requiring very little sample. It is primarily used to determine the purity of a compound. A pure solid will show only one spot on a developed TLC plate. In addition, tentative identification of the unknown compound can be made through TLC analysis.

How do you calculate Rf values in TLC?

In thin-layer chromatography, the retention factor (Rf) is used to compare and help identify compounds. The Rf value of a compound is equal to the distance traveled by the compound divided by the distance traveled by the solvent front (both measured from the origin).

How long should you run a TLC plate for?

Question: How Long Should You Run A TLC Plate For? Until The Solvent Front Is About Half Way Up. Until The Solvent Front Is At The Top Of The Plate. 2 Minutes.

What are the limitations of TLC?

Limitations of TLC Although it is a very simple and convenient technique, one of its limitations is that it cannot tell the difference between enantiomers and some isomers. Another disadvantage of TLC is that in order to identify specific compounds, the Rf values for the compounds of interest must be known beforehand.

What does a high RF value mean?

A high Rf (Ie 0.92) would refer to a substance that is very non-polar. Ie that substance moved a 92% of the entire distance the solvent traveled. A low Rf value (0.10) would refer to a substance that is very polar.

Can two compounds have the same Rf value?

The Rf can provide corroborative evidence as to the identity of a compound. … If two substances have the same Rf value, they are likely (but not necessarily) the same compound. If they have different Rf values, they are definitely different compounds.

What happens if a TLC plate is allowed to develop too long?

Chemicals move up a TLC plate along with the solvent being used to develop the plate. … This means that if left long enough, the chemicals will all merge together at the top of the plate, eliminating any separation that you could have seen on the plate.

How do you determine the best solvent for TLC?

Solvent (Mobile Phase) Proper solvent selection is perhaps the most important aspect of TLC, and determining the best solvent may require a degree of trial and error. As with plate selection, keep in mind the chemical properties of the analytes. A common starting solvent is 1:1 hexane:ethyl acetate.

What is the result of applying too much of your sample to your TLC plate?

If the TLC plate runs samples which are too concentrated, the spots will be streaked and/or run together. If this happens, you will have to start over with a more dilute sample to spot and run on a TLC plate.