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What’s the MATTER: Classify Changes of Matter. Matter, Classify Changes of Matter At the conclusion of our time together, you should be able to:. Characterize various changes of matter Recognize that a change of state in matter is a physical change. Interesting Signs:.
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Matter, Classify Changes of Matter At the conclusion of our time together, you should be able to: Characterize various changes of matter Recognize that a change of state in matter is a physical change
Physical Change Physical • A change in matter from one form to another without changing its chemical properties • (most can be reversed) • No change in atoms/molecules
Physical Change • Examples = • Change in state or phase change • Dissolving • Compressing • Light emission/absorption • Electrons passing through metals
Physical Change More Examples = • boiling of a liquid • melting of a solid • dissolving a solid in a liquid to give a homogeneous mixture • making a solution
2 1 Chemical Change Chemical • Bonds are made / broken • Change in oxidation states Li +1 Cl-1 Cl-1
Examples of Chemical Change • Chemical change or chemical reaction — transformation of one or more atoms or molecules into one or more different molecules. • Burning hydrogen (H2) in oxygen (O2) gives H2O.
Sure Signs of a Chemical Change“Chemists Get Practice Trying Labs” • Color Change • Gas Produced (not from boiling!) • Precipitate – a solid formed by mixing two liquids together • Temperature Change • Light
Remember the Law of Conservation of Mass • In a physical change or a chemical reaction, mass is neither created or destroyed (Antoine Lavoisier)
Matter, Classify Changes of Matter Let’s see if you can: Characterize various changes of matter Recognize that a change of state in matter is a physical change
Physical vs. Chemical Change • physical • chemical • physical • physical • chemical • Examples: • melting • flame produced • paper cut • dissolving salt in water • tarnishes in air
Physical vs. Chemical Change • chemical • physical • chemical • physical • physical • Examples: • rusting iron • mixing mud and water • burning a log • freezing water • grinding spices
A difference between physical change and chemical change is that • chemical change involves energy while physical change does not. • physical change involves energy while chemical change does not. • different kinds of molecules are present after a physical change but not after a chemical change. • different kinds of molecules are present after a chemical change but not after a physical change
In making a pizza, which process involves a chemical change? Mixing spices for the sauce Slicing pepperoni for the topping Spreading cheese on the pizza Baking the dough to form the crust
All You Really Need To Know You Can Learn From Noah's Ark • Remember that the ark was built by amateurs; the Titanic was built by professionals. • Remember that woodpeckers inside are a larger threat than the storm outside.