Question

When silica gel is the stationary phase, the developing solvent moves ________ substances up the plate most rapidly.

A) Polar
B) Nonpolar
C) Both Polar and Nonpolar
D) Neutral

Answer 1

The developing solvent moves nonpolar substances up the plate most rapidly when silica gel is the stationary phase because of the weaker interaction between nonpolar substances and the polar silica gel.

Step-by-step explanation:

When silica gel is used as the stationary phase in chromatography, the developing solvent moves nonpolar substances up the plate most rapidly. This is because silica gel is polar in nature, allowing nonpolar substances to be less attracted to the stationary phase and therefore travel faster with the solvent front. Conversely, polar substances will have stronger interactions with the polar silica gel, slowing their migration up the plate.