What Is Gypsum

Gypsum

Gypsum is used to make wall-board and tiles because it resists fire and water so well and because it insulates a building against both heat and cold. The boards or blocks of gypsum can be nailed and sawed like wood. A mixture of gypsum with a little cement and certain other materials forms a light building material … Read more

What Is Fallout

fallout

The dust and other materials that are in the air as the result of a nuclear explosion—that is, from atom bombs—is fallout. It contaminates, or poisons, the air, soil, and water. Fallout contaminates the world around us because it is radioactive. This means that it contains certain kinds of atoms that are breaking down. As … Read more