Explanation:
An element is a substance that is made up of only one type of atoms. It cannot be broken down into simpler substances.
For example, sodium, aluminium, nickel etc are all elements.
Whereas when two or more different elements combine together then it results in the formation of a compound.
For example, [tex]MgCl_{2}[/tex] is a compound.
Therefore, we can conclude that a substance that cannot be broken down into simpler substances by chemical or physical means is called an element.
A substance that cannot be broken down into simpler substances by any chemical or physical means is called a: chemical element.
A chemical element can be defined as a pure substance that comprises atoms having the same atomic number (number of protons) in its nuclei and as such it is the primary constituent of matter.
Basically, a chemical element is a pure substance that can't be broken down, decomposed or transformed by into simpler substances chemical or physical means.
In Chemistry, some examples of a chemical element include the following:
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