Particle Being Attracted to Empty Pore on Surface of the Activated Charcoal

NameDateClass

Carbon Chemistry ■ Enrich

Charcoal

Particle being attracted to empty pore on surface of the activated charcoal

Particles stuck to the surface of the activated charcoal

Empty pores

Grain of Activated Charcoal

If you’ve ever built a campfire or a fire in a fireplace, you know what is left after the fire goes out—charcoal. Charcoal is the black material formed when wood is burned. It is actually an impure form of graphite. Charcoal has lots of very small openings, or pores, throughout its structure. Another form of charcoal, called activated charcoal, is made by burning wood at very high temperatures with very little air. This process produces an even greater number of these extremely small pores throughout the charcoal.

Because of the tiny pores throughout the material, charcoal and activated charcoal are very useful. These openings can attract molecules and make them stick to their surfaces as shown in the figure above.

Activated charcoal can be used to remove harmful chemicals and bacteria from drinking water. It is also used in aquarium filters to keep the water in the tank clean. As the water flows through the pores in the activated charcoal, some of the substances in the water, such as pesticides, bacteria, and particles, are attracted to the surfaces of the pores. These materials then stick to the charcoal and are removed from the water.

Answer the following on a separate sheet of paper.

1.Another use for activated charcoal is in treating people and animals who have swallowed poisonous substances. How do you think activated charcoal removes a poison from a person’s or an animal’s body?

2.As well as removing particles from water and other liquids, activated charcoal can also remove particles from the air. Give examples of how activated charcoal might be used in this way.

3.Some backpackers carry a special kind of straw with them that contains a small filter made of activated charcoal. The straw is for use when clean drinking water is not available. How can the special straw be used to obtain clean drinking water?

4.Bacteria that is removed from drinking water by activated charcoal remains stuck to the surface of the charcoal. If the same activated charcoal is used for a long period of time to remove bacteria, a quantity of bacteria can build up on it. Manufacturers of drinking water filters made of activated charcoal recommend that the filter material be changed at least once a year. Why do you think this is a good idea?