Question

Why does acetone speed up the rate at which fluorenone travels?

Answer 1

I think this is related to the chromatography technique.

Fluorenone is having C=O group which cause little dipole movemnt to the molecule. This is the reason this molecule exhbit polarity.

Acetone is a good polar solvent.

We know that polar molecules love the polar solvent and move along with them in compare to non polar solvents like heane.

So by adding acetone to the non polar solvent, increases the polar nature of the mobile phase/ solvent, so the fluorenone travels faster than the non polar solvent alone.