Elements are substances that cannot be separated into simpler substances. Salt is made up of the elements sodium and chloride. Water is made up of the elements hydrogen and oxygen.
The smallest particles of matter are called atoms. Remember the carrot from the other chapter. If you continue to chop a carrot into smaller and smaller pieces, eventually you would reach a point where you could not cut up the carrot anymore, but still have carrot. You would then have molecules of carrot. The same applies to elements. If you continually cut up a piece of aluminum, you will reach a point that you could no longer divide it. These are aluminum atoms. An atom is the smallest particle of an element that has the properties of that element. Some properties of aluminum are: shiny, silver colored, fragile, and thin. Each element has its own type of properties.
Chemists use symbols to represent elements. A symbol is a letter or picture used to represent something. Chemists use one or two lettters to represent elements. The symbol for aluminum is Al. The symbol for oxygen is O.
Used mainly in the context of Geography a Constructive force is involved in making new land while a Destructive force breaks the land. As they are carrying opposite functions to one another they are considered as competing forces.
