Study of Matter Compounds  Elmhurst College
Atoms Physical Properties Mixtures  Chemistry Department
Elements Chemical Properties    Virtual ChemBook


What is an Element?


An ELEMENT is the simplest form of matter which can not be changed further by chemical or physical methods. An ATOM is the simplest form of an element.

 The simplest form of some elements is a MOLECULE. When an element consists of two identical atoms it is called a diatomic molecule. For example oxygen in air consists of molecules containing two atoms of oxygen, (written as O2).
All natural matter is composed of atoms containing some 92 elements. Another 10-12 elements are man-made. A number of elements exist in a pure form in nature such as oxygen and nitrogen (in air), gold, silver, carbon (graphite and diamonds), and sulfur. A few very familar elements include: iron in steel, copper in pipes in your house or the copper coating on pennies, and aluminum popcans.
 The elements are arranged into a table called the PERIODIC TABLE OF THE ELEMENTS. There are many web based versions of the table, with one of the best called WebElements.



 Hydrogen  Lightest by weight, a gas not found in air, very flammable

 Carbon  "Lead" in pencils - graphite, diamonds

 Nitrogen  Gas present in air, used as a liquid in demonstrations

 Oxygen  Gas present in air, reacts with most other elements

 Sodium  A soft silvery metal, very reactive in water

 Magnesium  Grey metal, used in alloys

 Aluminum  Grey metal used in beverage cans

 Sulfur  A yellow solid, reacts with many elements

 Chlorine  Used in tap and pool water to kill bacteria, a pale yellow gas

Copper  Orange/brown metal used in pipes

Zinc  Grey metal used to coat iron as in galvanized iron

Iodine  Purple solid, gives blue color with starch