Which, 9-fluorenol or 9-fluorenone, would have a lower Rf value on a silica gel place with 30% acetone/70% he?

9-fluorenol would have the lower Rf value because it is polar (look at the structure, it has an OH bond, while 9-fluorenene has an O double bonded to a carbon). The more polar molecule would stick to the silica gel, resulting in a lower Rf value.