Chapter 3: Matter – Properties and Change

A. Properties of Matter Substance Examples: – matter that has a uniform composition Examples: water table salt gold copper Things that are not substances: Salt Water Samples from different areas have different composition

A. Properties of Matter Cont. Physical Property Can be observed or measured without changing the sample’s composition Density Color Taste Hardness Boiling Point

A. Properties of Matter Cont. Chemical Property Ability of a substance to combine or change into another substance Does it burn in air? Does it react with water? Does it react with nothing?

B. States of Matter 4 states of matter Solid Liquid Gas Plasma

Compressibility: Can you compress it? B. States of Matter Compressibility: Can you compress it? NO NO YES

Practice Physical or chemical property? Iron and oxygen forming rust Iron is more dense than aluminum Magnesium burns brightly when ignited Hemoglobin binds with oxygen Mercury melts at -39oC

Practice Match the states of matter with the following descriptions: (1) solid (2) liquid (3) gas A. takes the volume and shape of its container B. has a definite volume but an indefinite shape C. has a definite volume but an indefinite shape

C. Physical vs. Chemical Changes Physical Change Does not change the substance Substance may seem different, but the way the atoms link up is the same Chemical Change A new substance forms Changes the way the molecules link up

It’s a physical change if… D. Physical Changes It’s a physical change if… It changes shape or size It dissolves It changes phase Freezes, boils, evaporates, condenses

It’s a chemical change if… E. Chemical Change It’s a chemical change if… A gas is produced (bubbles) A change in color A change in temperature A precipitate forms Light is produced New odor Explosion

Mixes vinegar and baking soda Practice Physical or Chemical Change… Crumpling Paper Burning Paper Cutting wood Crushing a can Melting Ice Rusting Mixes salt and water Mixes vinegar and baking soda