Answer:
Naphthalene
Explanation:
The compound that would come off the column first when a mixture of naphthalene and benzaldehyde is separated using Silica gel is ; naphthalene
This is because naphthalene is a Non-polar compound while Benzaldehyde has a polar covalent bond in it ( C = O ). silica gel been a polar absorbent makes it possible for the compound with more polar bond to be retained longer than a compound that is Non-polar
