CHEM 101 Dr. Ashe Chapters 1 & 2 IUP New Concept-in bold Key Term Remember Scientific Method Observations: natural phenomena and measured events Hypothesis: tentative proposal that explains observations Experiment: test if hypothesis is correct or not Model (theory): saying how things work Further experiment: test theory further Chemistry is the study of:  Matter o It’s properties o The changes it undergoes  The energy associated with it Matter has mass + volume Properties- unique characteristics that each substance has  Color, transparency  Density, electrical conductivity  Melting, boiling Composition types & amounts of simpler substance makes up a bigger chunk of matter Classification of matter: states Solid  Fixed shape and volume  May be hard or soft, rigid, or flexible  Organized atoms Liquid  Varying shape o Conforms to shape of container  Fixed volume  Atoms move around more Gas  Varying shape o Conforms to shape of container  No fixed volume  Atoms more freely Physical vs. Chemical properties Physical properties  Properties a substance has or demonstrates by itself without interacting with other substances  Color, melting point, freezing point, and density Chemical Properties  Transforms from one substitute to another  Flammability, corrosiveness, and corrosion resistance Intensive and Extensive property - An extensive property depends on the quantity of the material being desc