Matter made up of a single kind of atom is referred to as an element. Atoms are defined as the smallest particles of a given element that still express the element's chemical signatures.
Elements are substances that are distinguished by atomic number and are composed of a pure atomic substance. They are separated into various categories depending on whether they are metals, metalloids or nonmetals.
Examples of matter composed of a single type of atom include:
- Diamonds, composed of carbon atoms
- Phosphorus, composed of phosphorous atoms
- Chlorine gas, composed of chlorine atoms
Other forms of pure carbon include the Buckminster Fuller ball formation known as a fullerene, which is a combination of 60 carbon atoms. Elements like chlorine have no pure form but gas and cannot be stabilized in any other way. Elements like argon have molecules made solely of argon and are referred to as monoatomic.
A molecule composed of a single type of atom is called an allotrope. In combination, they may form several differing states depending on external conditions. The study and use of elements in human society runs all the way back to metallurgy and the advent of metal-working and the use of gold in currency and decoration, both of which paved the way to a modern era in which all non-radioactive elements are available in relatively pure forms to the general public.