* Sodium (Na): This is a pure element, not a compound. Elements are the simplest forms of matter and cannot be broken down further by chemical means.
* Sugar: This is a bit tricky. "Sugar" is a general term. Most commonly, it refers to sucrose (C₁₂H₂₂O₁₁), which is a pure compound. However, there are other types of sugars (like glucose and fructose) that are also pure compounds.
* Oxygen (O₂): This is a pure element in its diatomic form (meaning two oxygen atoms bonded together).
* Air: This is a mixture, not a pure compound. Air is primarily composed of nitrogen, oxygen, and other gases.
* Iron (Fe): This is a pure element.
Key Point: A pure compound is formed when two or more different elements combine chemically in a fixed ratio.
Let me know if you have any other questions!
