Physical and Chemical Changes

Physical and Chemical Properties Everything around us has physical and chemical properties.

Physical Properties vocabulary word! physical property - characteristic you can observe without changing the substance into something new. Use your senses to describe state of matter measurement

Use your senses… How does it look, smell, sound, feel, taste (don’t taste it unless the teacher says it’s ok)

What state of matter is it? (solid, liquid, or gas)

Measure it….mass, weight, volume, length, width, height, density, temperature, magnetic?

Chemical Properties vocabulary word! chemical property - characteristic that you can only observe by changing the substance into something new. You can’t always tell chemical properties just by looking Will it burn, explode, react with other elements?

Physical and Chemical Changes Matter around us can undergo changes. Physical Changes Chemical Changes

Physical Change vocabulary word! physical change - a change in which the form or appearance of matter changes but not its composition Change of state Change of shape Dissolving

Physical Changes changing state melting – solid to liquid condensation – gas to liquid freezing – liquid to solid sublimation – solid to gas vaporization – liquid to gas deposition – gas to solid

Changes in States

Physical Changes change of shape Matter can change shape cutting tearing grinding crumpling bending

Physical Changes dissolving When you mix or dissolve one thing into another, it is a physical change.

Chemical Change vocabulary word! chemical change - a change in which the composition of matter changes and new substances are formed. It cannot be turned back into the original substance

Chemical Change Signs that a chemical change may have taken place: color change absorption or release of energy odor formation of gases or solids can’t be reversed

Chemical Changes Iron + oxygen and water = rust silver + oxygen and water = tarnish

Chemical Changes Burned wood Cooked food

Chemical Changes Leaves turning in fall Spoiled food

Chemical Changes Lightning bug Antacid tablet

Physical or Chemical orange Orange juice Orange cake Copper jewelry Statue of Liberty copper Physical Chemical

Law of Conservation of Mass The total mass of matter before and after a physical or chemical change is the same. Matter cannot be created or destroyed The particles inside the matter rearrange to form new substances

Law of Conservation of Mass Even though it appears that part of the candle disappears, it is just turned into a gas. proven by Antoine Lavoisier

Directions: Take out all of the laminated cards Directions: Take out all of the laminated cards. Find the “Physical Change” and “Chemical Change” cards. As a table, look at the picture and read the description on the back. Decide whether your group thinks each one is a physical change or a chemical change. Physical Change Chemical Change