Elements:
* Metals: Gold (Au), Silver (Ag), Copper (Cu), Iron (Fe)
* Nonmetals: Carbon (C), Oxygen (O), Nitrogen (N), Chlorine (Cl)
* Metalloids: Silicon (Si), Boron (B), Germanium (Ge)
Compounds:
* Inorganic: Water (H₂O), Sodium chloride (NaCl), Carbon dioxide (CO₂)
* Organic: Ethanol (C₂H₅OH), Glucose (C₆H₁₂O₆), Methane (CH₄)
Important Notes:
* Pure substances have a fixed composition. This means they always contain the same elements in the same proportions.
* Pure substances have distinct properties. These properties can be used to identify and differentiate them.
* A mixture contains two or more substances that are not chemically combined. Examples of mixtures include saltwater, air, and sand.
Let me know if you'd like to explore specific examples in more detail!
