Question

in the gel filtration experiment, what would be the effect if the column length is doubled?

Answer 1

Gel filtration experiment used to separate molecules on the basis of their molecular mass or, more properly, their Stokes radius. It has nothing to do with column length. Only thing is that you will require more solvent as eluent. Choose a column of the proper size for the separation of the molecules. Volume of column needs to be 20 to 50 times than that of the sample to be applied. Tall thin column with length 20-40 times their diameter can be used. Make sure your column does not run dry by continually adding mobile phase to the top.