Physical Property Can be observed or measured without changing the matter’s identity Does not involve a chemical change Examples: Density Color Hardness Ductility Malleability Solubility Size Texture

Density m D v The amount of matter in a given space or volume Mass divided by volume Units: g/mL Knowing the density can tell you if an object will float or sink in water If object is less dense then water, it will float If object is more dense then water, it will sink m D v

Physical Changes A change that affects one or more physical properties of a substance Does not change chemical properties Examples: Crushing a can Melting ice Painting a wall Sanding wood Sugar water Ripping paper

Chemical Properties Describes matter based on its ability to change into new matter that has different properties. Flammability Ease of a substance to ignite Reactivity Ability of a substance to undergo a chemical reaction With Oxygen With Acid Combustibility Ability of a substance to explode or implode

Chemical Properties vs Chemical Changes When one or more substances are changed into new substances that have new and different properties it is a chemical change Chemical properties of a substance describe which chemical changes will occur and which chemical changes will not occur Chemical changes are the process by which substances actually change into new substances.

Chemical Change Signs of chemical change: Color change Gas production Change in temperature Precipitate formed (precipitate – a solid formed from solution) Change in overall properties Chemical changes are hard to reverse Some chemical changes can be reversed by more chemical changes

Physical vs Chemical Did the composition/identity change? The composition/identity of an object is the type of matter that makes up the object and the way that the matter is arranged in the object Physical changes do not change the composition of a substance Chemical changes do alter the composition of a substance