1. Chapter 2 – Properties of Matter Section 1 – Classifying Matter

2. Key Objectives Why are elements and compounds classified as pure substances? How do mixtures differ from pure substances? What is the main difference among solutions, suspensions, and colloids?

3. Matter Chart

4. Substances Matter that always has the same composition Table Salt Table Sugar Classified into two categories Elements Compounds

5. Elements A substance that cannot be broken down into simpler substances Chopping copper into extremely small particles Atoms – Smallest particle of an element No two elements have the same type of atom

6. Element Examples Oxygen Aluminum Iron Gold

7. Compounds Substance composed of 2 or more elements and can be broken down into those elements Water Oxygen and Hydrogen Sodium Chloride (Salt) Sodium and Chlorine

8. Mixtures Unlike a substance, a mixture does NOT have a fixed composition The parts are not spread evenly throughout it Heterogeneous Mixtures Homogeneous Mixtures

9. Heterogeneous Mixtures The parts are noticeably different from one another You can see the different parts Salsa Sand M&Ms Mixed Vegetables

10. Homogeneous Mixtures Difficult to distinguish the different parts Appears to contain only one substance Tap Water Kool-Aid Air

11. Mixture Types Based on the size its largest particles, a mixture can be classified as a Solution Suspension Colloid

12. Mixture Types Solution – Substances dissolve and form a homogeneous mixture Sugar and Water Suspension – A heterogeneous mixture that separates into layers “ Shake well before using ” Colloid – Mixture of a suspension and a solution Milk