A substance is a general term for any form of matter that has a uniform and definite composition, while an element is a specific type of substance made up entirely of one kind of atom. In other words, an element is a pure substance consisting of only one type of atom, and it cannot be broken down into simpler substances by chemical means. A substance can be either an element or a compound (which consists of atoms of two or more different elements chemically bonded together).
Key Differences
- Element: Made of only one type of atom; pure substance; cannot be chemically broken down into simpler substances.
- Substance: Can be either an element or a compound; has uniform composition and distinct properties.
Examples
- Oxygen (O2) is an element because it contains only oxygen atoms.
- Water (H2O) is a compound substance made of hydrogen and oxygen atoms chemically bonded.
Thus, what makes a substance different from an element is that an element refers specifically to one type of atom, while a substance can be a pure element or a compound made of multiple elements chemically combined.
