SubstancePhysical PropertyChemical Property HeliumLess dense than airNonflammable WoodGrainy textureFlammable Baking sodaWhite powderReacts with vinegar to produce bubbles Rubbing alcoholClear liquidFlammable Red food coloringRed colorReacts with bleach and loses color IronMalleableReacts with oxygen

 A chemical change is a change in matter in which the substance that makes up the matter changes into something else with different chemical AND physical properties! **A NEW SUBSTANCE IS CREATED!!**  All reactions involve energy (light, sound, or thermal) - Some require it to start, some give off energy, and some absorb energy.

 Change in Odor  Change in Temperature  Formation of Bubbles/Gas  Change in Color  Formation of a Precipitate (solid that forms when two liquids combine)