Question

What is the difference between pure substances and elements?

Answer 1

An element is basically a substance that is made up of the same kind of atoms. It can be called a pure substance too. But elements are not the only kind of pure substances.
All pure substances are NOT elements. A pure substance is one whose building blocks are heterogenous in nature. That is, the atoms or molecules that make it are of the same type. But unlike elements, the building blocks of pure substances are not restricted only to atoms. Certain compounds are called pure substances too.
Example for element: All the members on the periodic table:Hydrogen, Helium...............
Example for pure substances: certain oils, metals WITHOUT extraneous impurities etc etc...........