Elements compounds and mixture
1. Elements
Definition: An element is a pure substance made of only one kind of atom.
Examples:
Oxygen (O) – we breathe it
Iron (Fe) – used to make tools
Gold (Au) – used in jewellery
Main point:An element cannot be broken into simpler substances.
2. Compounds
Definition:A compound is a substance made when two or more elements join together in a fixed ratio.
Examples:
Water (H₂O) = Hydrogen + Oxygen
Salt (NaCl) = Sodium + Chlorine
Carbon dioxide (CO₂)
Main point:A compound has new properties different from the elements in it.
3. Mixtures
Definition: A mixture is made by mixing two or more substances without any chemical change.
Examples:
Air (many gases mixed)
Sand and salt
Fruit salad
Main point:The substances in a mixture can be separated easily.
Fun Fact:
Air looks like one thing, but it is actually a mixture of many gases!