Question

State the properties of charcoal which are used in gas masks and water filters.

Answer 1

Gas Mask: A gas mask is a protective mask used to cover the face of a person as a defense against poison gas.

Used of charcoal in a gas mask:

• Charcoal is carbon.
• Activated charcoal is charcoal that has been treated with oxygen to open up millions of tiny pores between the carbon atoms.
• When a material adsorbs something, it attaches to it by chemical attraction.
• The huge surface area of activated charcoal gives it countless bonding sites.
• When certain chemicals pass next to the carbon surface, they attach to the surface and are trapped.

Use of charcoal in water filters:

• Water filters use a special type of charcoal known as 'activated charcoal' to purify water.
• Activated charcoal works through the process of adsorption.
• Note that adsorption is different from absorption.
• Adsorption binds impurities chemically on the surface of the charcoal filter rather than physically absorbing them.