On the application of n-hexane and ethyl acetate in thin layer chromatography
TLC, a commonly used method for chemical analysis, can identify various components in the mixture. N-hexane and ethyl acetate are widely used in TLC, and the reasons are as follows.

For n-hexane, a non-polar solvent is also used. Its molecular structure is simple, the charge distribution is uniform, and the polarity is weak. In TLC, non-polar or weakly polar compounds can migrate with the mobile phase. Because of the similar compatibility, non-polar compounds are easily soluble in non-polar n-hexane, so when n-hexane is used as the mobile phase, such compounds move quickly and can be separated from polar compounds on thin-layer plates.

Ethyl acetate has a certain polarity. Its molecular structure contains polar functional groups, which can interact with polar compounds. In TLC, the polarity of the mobile phase can be adjusted. When only n-hexane is used, the polarity of the mobile phase is low, and some compounds with slightly stronger polarity are difficult to migrate, resulting in poor separation effect. Adding ethyl acetate can increase the polarity of the mobile phase, so that the polar compounds can move a suitable distance and achieve good separation effect.

The combination of n-hexane and ethyl acetate can adjust the ratio of the two according to the polarity difference of the compounds in the sample to obtain the best separation conditions. If the sample contains non-polar and weakly polar compounds, n-hexane can be added to reduce the polarity of the mobile phase, so that the compounds of different polarities have significant location differences on the thin layer plate; if the polarity of the sample is slightly stronger, the proportion of ethyl acetate can be increased, the polarity of the mobile phase can be increased, and the polar compounds can migrate and separate.

Furthermore, the boiling point of the two is suitable. The boiling point of n-hexane is about 69 ° C, and the boiling point of ethyl acetate is about 77 ° C. This boiling point is convenient for removing the mobile phase after the experiment, and there is no residue, which does not disturb the subsequent analysis of the sample. And the two have good volatility. After the thin layer plate is unfolded, the mobile phase is

In summary, n-hexane and ethyl acetate are commonly used mobile phases in thin-layer chromatography due to their polar complementarity, suitable boiling point, and good volatility, which can help researchers effectively separate and analyze the components of the mixture.