Unit b matter and chemical change notes (classifying matter)
- 2. Classifying Matter Pure Substance: • is made of only one kind of matter • has a unique set of properties that sets it apart from any other kind of matter. • (It is further classifies into an element or a compound) Mixture: • is a combination of pure substances not combined chemically
- 3. Pure Substances Element (Example Na or Sodium/O or Oxygen): • Matter than cannot be broken down into any simpler substance. • The most purest matter because it contains only one kind of atom • Represented by a symbol on the periodic table Compounds (H20 or CO2) : • A substance formed by 2 or more elements chemically fixed in proportion (molecule).
- 4. Pure Substances Compounds (H20 or CO2) : • A substance formed by 2 or more elements chemically fixed in proportion (molecule: atoms bonded together).
- 5. Mixtures Mechanical Mixture (Heterogeneous): • Some or all particles can be seen and be separated (Ex. Salad) Solution (Homogeneous): • Not separate visibly, as one is dissolved in another (Ex. coffee) • A substance dissolved in water is called an aqueous solution
- 6. Mixtures Suspension: • Mixture where tiny particles of one substance are held within another. Substances can be separated by centrifuging or filtration. (Ex. Salad dressing) Colloid: • Cloudy mixture, where the particles are suspended and difficult to separate (Ex. milk)
- 7. Tyndall Effect Solution vs Colloid Solution vs Colloid
- 9. 1. How is an element different than a compound? Give an example of each. 2. What is the difference between a pure substance and a mixture? 3. How is a suspension different from a colloid? 4. Classify the following substances as an element, compound, or mixture: a) Pop is composed of water, sugar, and carbon dioxide. b) Graphite in a pencil is composed of carbon. c) Carbon dioxide is composed of carbon and oxygen.