TLC and Column Chromatography Part I CHEM2050

[SCIGEEK15]

dont you mean if the compounds are leaving to quickly you must make the mobile phase more polar? and vice versa if the compounds are leaving to slowly you must make mobile phase more no-polar? 1:38min

[fanchemii]

@SCIGEEK15 no, what she said is right. Don't forget that the stationary phase (silica or alumina) is polar. So polar compounds bond more strongly to the polar stationary phase. If the compounds are leaving too quickly, it means that the solvent is too strong as the compounds are interacting with it rather than the stationary phase. Hope that clears it up a bit.