Element vs. Compound: What's the Difference?
Both are pure substances, but the difference is what they're made of. An element contains only one kind of atom and can't be broken down chemically — like gold or oxygen. A compound is two or more different elements chemically bonded in a fixed ratio — like water (H₂O), which is hydrogen and oxygen combined.
See the difference, explained visually.
Watch a 2-minute animated lesson comparing element and compound.
At a glance
| Element | Compound | |
|---|---|---|
| Made of | One kind of atom | Two or more different elements |
| Breaks down chemically? | No | Yes — into its elements |
| Example | Oxygen (O), gold (Au) | Water (H₂O), salt (NaCl) |
| Properties | Its own | Often unlike its elements |
| On the periodic table? | Yes — all 118 are listed | No — compounds aren't listed |
Which should you use?
Element
It's an element when the substance is made of a single type of atom and appears on the periodic table — like carbon, iron, or helium.
Compound
It's a compound when two or more different elements are chemically bonded in a set ratio, creating a new substance with its own properties — like water or carbon dioxide.
Frequently asked questions
- Is water an element or a compound?
- Water is a compound — it's made of two elements, hydrogen and oxygen, chemically bonded as H₂O. It can be split back into those elements by electrolysis.
- What's the difference between a compound and a mixture?
- A compound's elements are chemically bonded in a fixed ratio, forming a new substance; a mixture's parts are only physically combined and keep their own properties, so they can be separated physically.
- Can a compound be broken into elements?
- Yes, but only by a chemical reaction — for example, passing electricity through water separates it into hydrogen and oxygen gas.