Elements and compounds are used all around you. The toothpaste you use, the detergent in your kitchen, and the fluid in your car battery are examples of how you use elements and compounds. Everything around us, including our own bodies, can be broken down into the elements that are found in the periodic table.

In this activity, you will look closely at compounds.

You know that the periodic table lists elements. A substance made up of two or more different elements chemically combined together is known as a compound.

• Oxygen is a pure substance that consists of a single element.

• Salt is a pure substance that consists of more than one element. Salt consists of the elements sodium and chlorine joined chemically.
  

Most substances in the world are compounds.

 Compounds can be broken apart into simpler substances. This is done through a process called decomposition reaction. This is like taking a clock apart into the parts that make it up.

 These reactions often involve an energy source such as heat, light, or electricity that breaks apart the bonds of the compounds.