Presentation on theme: "Physical and Chemical Changes"— Presentation transcript:
1Physical and Chemical Changes How can you to tell the difference???
2Physical changes are those changes that DO NOT result in the production of a new substance.
3If you melt a block of ice, you still have H2O at the end **If you melt a block of ice, you still have H2O at the end. **If you break a bottle, you still have glass. **Painting your nails will not stop them from being fingernails.
4Some, but not all physical changes can be reversed Some, but not all physical changes can be reversed. You could refreeze the water into ice, but you cannot put your hair back together if you don’t like your haircut!
5Physical ChangeSubstance may seem different, but the way the atoms link up is the same.
6It’s a physical change if… It changes shapeIt changes size
9CHEMICAL PROPERTIESChemical properties can ONLY be observed AS the substances are changing into different substances.
10FLAMMABILITY: A material’s ability to BURN in the presence of OXYGEN
11REACTIVITY: How readily (easily) a substance combines chemically with other substances.
12Chemical Change Changes the organization of atoms and molecules Makes new substances
13When you burn a log in a fireplace, you release carbon **When you burn a log in a fireplace, you release carbon. **When you light your Bunsen burner in lab, you produce water and carbon dioxide. **When you mix baking soda and vinegar, you produce CO2.
14It could be a chemical change if…. It burnsProduction of heat or lightTemperature changes without heating/cooling
15It could be a chemical change if... It bubblesIt produces a gas
16It could be chemical change if... Production of sound
17It could be chemical change if... It changes propertiesChange in odor or taste
18It could be chemical change if... It changes color
19It’s a chemical change if... It forms a precipitateIt forms a new substance
20Common examples of chemical changes… digestion, respiration, photosynthesis, burning, and decomposition.
21Physical or Chemical Change? Painting a wood block redPHYSICAL
22Physical or Chemical Change? Burning PaperCHEMICAL
23Sugar dissolving in water PHYSICAL Physical or Chemical Change?Sugar dissolving in waterPHYSICAL
24Iron turning red when heated PHYSICAL Physical or Chemical Change?Iron turning red when heatedPHYSICAL
25Physical or Chemical Change? EvaporationPHYSICAL
26A pond freezing in winter PHYSICAL Physical or Chemical Change?A pond freezing in winterPHYSICAL
27Physical or Chemical Change? Melting icePHYSICAL
28Physical or Chemical Change? Digestion of foodCHEMICAL
29Physical or Chemical Change? Cutting wirePHYSICAL
30Physical or Chemical Change? Mixing cake batterPHYSICAL
31Physical or Chemical Change? Cutting fabricPHYSICAL
32Physical or Chemical Change? Baking muffinsCHEMICAL
33Physical or Chemical Change? Shattering glassPHYSICAL
34Decomposition of old leaves CHEMICAL Physical or Chemical Change?Decomposition of old leavesCHEMICAL
35Physical or Chemical Change? Wrinkling a shirtPHYSICAL
36Physical or Chemical Change? An old nail rustingCHEMICAL