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2. Matter  Matter is….  Anything that has mass and takes up space (mass and volume)

3. States of Matter

4.  3 Main states of matter  Solid  Liquid  Gas  Scientists recognize a fourth state of matter called plasma, but it does not occur naturally on Earth except in the form of lightning bolts.

5. Solid  A solid -definite shape and volume.  Wood, iron, paper, and sugar are examples of solids

6.  The particles in a solid are very tightly packed; when heated, a solid expands, but only slightly.  Do you think a solid would conform to the shape of its container?  Not Likely

7. Liquid  A liquid is a form of matter that flows, has constant volume, and takes the shape of its container  water, blood, and mercury  The particles in a liquid are not rigidly held in place and are less closely packed than are the particles in a solid: liquid particles are able to move past each other.

8. Liquid  A liquid -flows, has constant volume, and takes the shape of its container  water, blood, and mercury  The particles are not rigidly held in place and are less closely packed than the particles in a solid  liquid particles are able to move past each other.

9.  Does a liquid take the shape of its container?

10. Gas  A gas -conforms to the shape of its container and fills the entire volume of its container.  the particles of gases are very far apart.  gases are easily compressed.

12. What can happen between these states?

13. Phase Changes  Phase changes occur when substances undergo change in temperature and pressure

14. Changes in States  Solid  Liquid  Melt  Liquid  Gas  Evaporate/Vaporize  Gas  Liquid  Condense  Liquid  Solid  Freeze  Solid  Gas  Sublime  Gas  Solid  Deposit

15. Physical/Chemical Properties

16. Physical Properties  Characteristics that can be observed without altering the identity of the substance. (First observation)  State, density, color, odor, melting point, boiling point, luster, conductivity, brittleness, malleability.

17. Chemical Properties  Characteristics that cannot be observed without altering the identity of the substance. (Something turns into something else)  Reactivity, flammability, reaction types

18.  Similarly, the inability of a substance to change into another substance is also a chemical property.  For example, when iron is placed in nitrogen gas at room temperature, no chemical change occurs.  The fact that iron does not undergo a change in the presence of nitrogen is another chemical property of iron.

19. Physical Changes  Physical Changes  Do not alter the identity of a substance  Crushing, tearing, changes of state (solid to liquid to gas) ** Dissolving a solid in liquid (reversible)**  Can you think of any others?

20. Chemical Changes  Chemical Changes  Alter the identity or chemistry of a substance  Burn, cook, rust, reacts with, explode, oxidize, corrode, tarnish, ferment, or rot:  Terms that generally refer to a chemical reaction

21. Chemical Changes  A chemical change is the same thing as a chemical reaction

22.  The new substances formed in the reaction have different compositions and different properties from the substances present before the reaction occurred.

23. Here’s an example  When a freshly exposed iron surface is left in contact with air, it slowly changes into a new substance, namely, the rust.

24.  Rust is a chemical combination of iron and oxygen.  In chemical reactions, the starting substances are called reactants and the new substances that are formed are called products.

25.  So in the rusty nail problem, what are the reactants and what are the products?  Reactants: Iron and Oxygen  Product: Rust

26. Even though old substances become new substances,  THE MASS STAYS THE SAME BEFORE AND AFTER THE REACTION!!!!

27. Conservation of Mass  Mass is never created or destroyed by a reaction! It is conserved! (This is a LAW)  The total mass in a reaction remains constant.  Mass Reactants = Mass Products

28.  How could you find this?  Measure mass of reactants and mass of products and compare…they should be equal.  Mass of the turkey, lettuce, mayo, tomato, and bread = mass of sandwich

29. Note Quiz  Get out 1 piece of paper per table. Write both your names on it and work together!  You will turn this in as a quiz grade.

30. Note Quiz  Identify each of the following as a property of a solid, liquid, or gas. Some answers will include more that one state of matter. 1. Flows and takes the shape of a container 2. Compressible 3. Made of particles held in a tightly packed, specific arrangement

31. 4. Has definite volume 5. Always occupies the entire space of the container 6. Has a definite volume but the particles flow 7. Phase change from solid  liquid 8. Phase change from gas  liquid

32. Notes Quiz  Identify each of the following as an example of a chemical change or a physical change. 9. Moisture in the air forms beads of water on a cold windowpane. 10. An electric current changes water into hydrogen and oxygen