Chapter 2 Section 2

• Can be observed or measured without changing the identity of the substance

• Examples•Thermal Conductivity: the ability to transfer thermal energy from one area to another•State: the physical form in which a substance exists•Malleability: the ability to be pounded into thin sheets

• Examples, continued•Ductility: the ability to be drawn or pulled into a wire•Solubility: the ability to dissolve in another substance•Density: mass per unit volume

• Is a characteristic property: can be used to help identify the substance

D VM

• Density differences will cause liquids to separate. • Densest layer will go to the bottom• Least dense will float on top• See page 46

• Describes a substance based on its ability to change into a new substance• Examples:•Flammability: ability to burn•Reactivity with oxygen (oxidation)•Reactivity with water•Reactivity with acid

• Properties that are always the same whether the sample is large or small• Helps to identify a substance because they never change• Example•Density•Solubility•Reactivity with acids

• A change that affects one or more physical properties of a substance• Often easy to undo• Examples•Cutting down a tree•Painting a house•Melting butter•Making an aluminum foil ball

• When one or more substances are changed into a new substance with new properties• Most chemical changes can not be undone• Examples•Soured milk•Camp fire•Rusting car•Baking cookies

• Color change• Fizzing or foaming (gas formed)• Heat (energy change)• Sound (energy change)• Light (energy change)• Odor• Precipitate- solid formed in a solution

• Properties- the substances ability to go through a chemical change

• Changes- the actual process in which a substance changes into another substance

• Observe chemical properties when a chemical change might occur