After reading this section you will be able to do the following:
- Be able to define an element.
- Be able to recognize and recall some of the basic elements.
An element defined
Any material that is composed of only one type of atom is called a chemical element, a basic element, or just an element. Any material that is composed of more than one type of atom is called a compound. Every element has a unique atomic structure. Scientists know of only about 109 basic elements at this time. (This number has a habit of changing.) All matter is composed of combinations of one or more of these elements. Ninety-one of these basic elements occur naturally on or in the Earth. The other elements are man-made. You may recognize the names of some of these basic elements, such as: hydrogen, helium, oxygen, iron, copper, gold, aluminum, uranium. The periodic table of elements (shown below) lists the basic elements and some of their properties.
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- An element is material composed of only one kind of atom.
- A compound is material composed of more than one kind of atom.
- Some examples of elements that can be found on the periodic table are hydrogen, helium, oxygen, iron, copper, gold, aluminum, uranium.