the definition of element
Definition of Element. An element is a substance consisting of atoms which all have the same number of protons - i.e. the same atomic number. Elements are chemically the simplest substances and hence cannot be broken down using chemical methods. Elements can only be changed into other elements using nuclear methods. Although an element's atoms must all have the same number of protons, they can have different numbers of neutrons and hence different masses. When atoms of the same element have different numbers of neutrons, they are called isotopes.