What is a property of matter? Characteristic of that type of matter Can be physical or chemical property Can be observed using your senses Cannot be observed with senses- must be tested or reacted with something

Physical Properties Examples: mass, color, shape, smell, volume, density, melting point, boiling point, and hardness.

Chemical Properties Examples: ability to burn, ability to decompose (food), ability to rust, how it reacts with other substances

Changing Matter Matter can be changed two ways: Physically Chemically

Physical Changes Do NOT CHANGE THE IDENTITY OF MATTER on a chemical level –Nothing new or different is formed –Could be a change in: Change in state Shape Color Size Volume Density Mass

Examples of Physical Changes Boiling Freezing Evaporation Dissolving Breaking Cutting Painting Making a mixture –2 or more substances physically mixed together Can be separated physically

Chemical Changes **A chemical reaction MUST take place! Matter changes at the atomic level (atoms separate and recombine in different ways!) and NEW SUBSTANCES are created!!!

Chemical Changes Molecules are bonding and “unbonding” –Atoms are re-arranged into different combinations –For example: CaCO 3 + heat  CaO + CO 2 (New Substances!! A chemical change took place!) **Did you lose any atoms?

Chemical Changes Rusting Burning Cooking Mixing acids & bases Food being metabolized in body (*where??) Baking Explosion of fireworks

Law of Conservation of Mass Atoms are just rearranged, NOT created or destroyed Mass is conserved  total amount of atoms cannot change –Nothing is ever created or destroyed!

Chemical Changes Molecules- may be made up of the same type of atom OR different types of atoms. (ex: H 2, H 2 O, CO 2 ) Compounds- made of up DIFFERENT types of atoms only. (ex: H 2 O, CO 2 but not H 2 !)