2. Matter What does it matter?

3. What is matter? Has mass (amount of atoms) Has volume (amount of space) Made from atoms Has chemical and physical properties Matter can change physically and chemically

4. Physical Properties Properties that can be observed without changing the identity Examples: size, color, density, smell, phase (solid, liquid, gas), mass, volume

5. Physical Changes Changes that only affect physical properties--atoms stay the same Phase changes--melting, freezing, condensation, evaporation, boiling Tearing, cutting, coloring, mixing

6. Chemical Properties Properties that describe how matter reacts (becomes something new). Burning, rusting,tarnishing, oxidizing, acid or base, reacting

7. Chemical Changes Changes that make a new substance A substance becomes something different Atoms are rearranged Burning, decomposing, dyeing, rusting Bread becomes toast Bleaching clothes

8. Examples Physical Change: CAT -> cat or cat -> cat Chemical Change: cat -> act or cat -> ca

9. Signs of a Chemical Change Bubbles produced New odor Temperature change Color change Solid produced