2. Elements
• There currently are 118 elements
• A element is a substance that cannot be broken down into simpler
substances
• A element has a fixed composition because it contains only one type of
atom
3. Pure Substances
• A pure substance is matter that always has the same composition.
4. Compounds
• A compound is a substance that is made from two or more simpler
substances
• The simpler substances are either elements or other compounds
• Oxygen is a compound
• Silicon is a compound
5. Mixtures
• The properties of a mixture can vary because the composition is not fixed.
• When ingredients are not evenly distributed.
6. Physical Properties
• Viscosity is the resistance to flowing .
• Conductivity is a materials ability to allow heat to flow through it.
• Malleability is the ability of a solid to be hammered without shattering
• Hardness can be compared by scratching two materials and seeing which
scratches which.
• Melting and boiling point
• Density can be used to test purity of a subject
7. Evaporation
• A process used to isolate a solid dissolved in a liquid
• Warning: You are not going to isolate all of the substances
8. Filtration
• A process that separates materials based on their sizes
9. Distillation
• A process that separates the substances in solution based on Boiling point
10. Flammability and
Reactivity
• Flammability is a material’s ability to burn is the presence of oxygen.
• The property that describes how readily a substance combines chemically
with other substances is reactivity.
• Flammability and reactivity are both qualitative results.
11. Recognizing Chemical
Change
• A change in color
• Production of gas
• Formation of a precipitate
12. Is a change chemical or
Physical
• When matter undergoes a chemical change, the composition of the matter
changes . When matter undergoes a physical change, the composition of the
matter remains the same.
