Notes Tennessee SPI Objective: Interpret the results of an investigation to determine whether a physical or chemical change has occurred. Science Essential Learning Students will examine scenarios and decide if a physical or chemical change has occurred. Essential Question(s) How do I tell the difference between a physical and chemical change? Instructions 1) First click on "View" from the top-menu bar. 2) Then click on "Slide Show" from the drop-down menu. 3) Then use the right-arrow button on your keyboard to advance through this presentation. SPI Physical or Chemical Changes

Physical Changes  A change of matter from one form to another without a change in chemical properties.  Changes the appearance of an object, but does not change the composition of the object.  In other words, the way it looks is changed, but what it is does not change. (kind of like dressing up for a costume party)  Physical changes do not form new substances.  Can be fairly easily undone or reversed Notes Science SPI Physical or Chemical Changes

Physical Changes: changes the appearance of an object, but does not actually change the composition of the object Physical Changes DO NOT Form New Substances! Notes Science SPI Physical or Chemical Changes Physical Changes Two Examples DO NOT

Physical Change: It looks different, but is still the same material. Liquid Water Solid Water Water Vapor H2OH2O H2OH2OH2OH2O Notes Science SPI Physical or Chemical Changes Example: Changes of state/phase ARE NOT chem reactions In other words, liquid to solid to gas are only physical changes No chemical reaction has occurred.

Examples of Physical Change  Melting  Freezing  Boiling  Bending  Cutting  Crushing  Tearing  Breaking  Smashing  Dissolving Notes Science SPI Physical or Chemical Changes In every example here, the appearance is changed, but the composition remains the same.

 Freezing Notes Science SPI Physical or Chemical Changes Physical Change Examples  Melting  Boiling For each of these examples, the appearance is changed, but the composition remains the same.

 Crushing Notes Science SPI Physical or Chemical Changes Physical Change Examples  Cutting  Tearing For each of these examples, the appearance is changed, but the composition remains the same.

 Smashing Notes Science SPI Physical or Chemical Changes Physical Change Examples  Breaking  Dissolving For each of these examples, the appearance is changed, but the composition remains the same.

5 Key Points About All Chemical Reactions: 1) A new substance is created 2) The properties of the new substance are different from the substances that you started with 3) No atoms are created or destroyed in chem reactions 4) Atomic bonds are broken and new bonds are formed (at the valence electron level) 5) compounds come from chemical reactions SPI Chemical Change Outcomes Notes Science Chemical Change Is the result of a chemical reaction & a new substance is formed  Can not be easily undone or reversed  Link: Chemical and Physical Changes-VideoChemical and Physical Changes-Video

Chemical Change Indicators-Memory Trick H.O.P.E.S. H: Heat-Heat may be given off (it may get hot) O: Odor/gas-There may be a change in odor (how it smells) P: Pop-It may pop or bang (make a loud noise) E: Explode-It may explode (like fire crackers or dynamite) S: Sound- Noise may be heard (snap, crackle, pop, sizzle, bang, boom) SPI Chemical Change Outcomes Notes Science Memory Trick H.O.P.E.S

Chemical Change Indicators-Memory Trick 4FPC F: Foam-It may foam (like vinegar & baking soda) F: Flash-It may flash (like a grenade or gun powder) F: Fizzle-It may fizzle (make a hissing sound like Alka-Seltzer) F: Flame- It may burn (like burning paper or wood) P: Precipitate-It may form a solid substance (called a precipitate) C: Color- It may change color (red to blue, green to orange, etc.) G: Gas- Gas may be released (may smell different) SPI Chemical Change Outcomes Notes Science Memory Trick 4FPCG

Notes Science SPI Physical or Chemical Changes Chemical Change Example Iron and oxygen react to form a compound called iron oxide.  Color Change: From silvery-gray to red-orange-brown 1966 VW Beetle Bare Metal-No Paint 1966 VW Beetle Rusting away

Notes Science SPI Physical or Chemical Changes Chemical Change Example Copper + oxygen react to form a compound called copper oxide.  Color Change: From golden-brown to aqua-marine green Statue of Liberty Original look-1886 Statue of Liberty Modern look-2014

Notes Science SPI Physical or Chemical Changes Chemical Change Example The Space Shuttle used solid rocket propellant called APCP Space Shuttle (USA) Lift Off Space Shuttle (USA) Lift Off  Burning APCP results in a very powerful chemical reaction

Notes Science SPI Physical or Chemical Changes Chemical Change Example Upset stomach? You can take Alka Seltzer effervescent tablets  Drop the tablets in water and you get a chemical reaction

Notes Science SPI Physical or Chemical Changes Chemical Change Example Soured milk is the result of a chemical reaction  Bacteria converts lactose to lactic acid

Here is an example of a question you might see on a quiz or test. Questions Science Sample Question SPI Physical or Chemical Changes

…a question you might see on a quiz or test. Questions Science Sample Question SPI Physical or Chemical Changes

Here is an example of a question you might see on a quiz or test. Questions Science Sample Question SPI Physical or Chemical Changes

…a question you might see on a quiz or test. Questions Science Sample Question SPI Physical or Chemical Changes

…a question you might see on a quiz or test. Questions Science Sample Question SPI Physical or Chemical Changes