Answer
See work below for details.
Work Step by Step
Heating wood in the absence of air produces charcoal. Charcoal contains a high amount of amorphous free carbon retains the general overall shape of the original wood.
Activated charcoal consists of fine particles, rather than a lump of charcoal, and subsequently has a much higher surface area. Activated charcoal is made by heating amorphous carbon in steam, which breaks the grains into smaller sizes and removes any other materials adsorbed on the surface.
