The document provides a review of various physics concepts including: - The metric unit for mass is grams. Matter with freely moving particles is a gas. The x-axis variable in data tables is usually represented by x. - Volume units include mL and cm3. Physical changes do not alter the identity of matter. - Density is a measure of mass within a volume. It is affected by how tightly packed particles are. Objects with the same volume but different masses have different densities.

3. Quick Review The metric unit for mass is? Which form of matter has particles that are free to move independently and collide frequently? Which variable is usually is represented by the x-axis in a data table? Give 2 unit labels for volume. Physical changes to matter do not change what?

4. Quick Review When CO 2(s) changes state directly into a gas without becoming a liquid, we call this______________. Which form of matter has both crystalline and amorphous structures? Plant leaves lose water through evaporation – physical or chemical ? Why? Proteins are made from amino acids – physical or chemical ? Why? Food is digested – physical or chemical ? Which Law states that Mass can neither be created or destroyed?

5. Quick Review What method would you use to find the volume of a block of wood? What are 3 equivalent formulas for finding the volume of a cube? What are the 3 equivalent units of measurement for volume of an object? When will a substance float in water? What is the vocabulary word for finding the volume of an irregularly shaped object?

6. Introduction to Density A substance’s density is the measure of the mass of material within a certain volume . (amnt of space taken up) The mass (amnt of particles) is affected by how tightly packed the molecules are within the space.

7. Introduction to Density A B A and B = SAME VOLUME (same size)

8. Introduction to Density A B A and B = SAME VOLUME (same size) A B A and B = DIFFERENT MASS (amount of particles; different substance) Different Densities

9. Introduction to Density C D C and D = DIFFERENT VOLUME (different size) but same substance

10. Introduction to Density C D C and D = DIFFERENT VOLUME (different size) but same substance Same Densities- particles are packed the same way

11. Let’s Review VOLUME – amount of space mL, cm 3 , cc DENSITY – how the particles are packed- RATIO g/mL , g/cm 3 , g/cc, kg/m 3 MASS – amount of particles Any gram unit Turn to the back of your handout – blank page

12. You will need this chart to ID substances. Sample Chemical Symbol Density g/cm3 Physical Attribute Lead Pb 11.3 Heaviest Mass Copper Cu 8.9 Orange Iron Fe 7.9 Magnetic/Rusts Brass Cu & Zn 8.6 Yellow Aluminum Al 2.7 Lightest Mass Zinc Zn 7.1 Dull Gray

13. Substance Mass (g) Volume (cm 3 ) Density (g/cm 3 ) 4. Cube 1= _________ 5. Cube 2 = _________ 6. Cube 3 = _________ Cube 4 = _________ 8. Cube 5 = _________ 9. Cube 6 = _________

14. Copy chart onto Cornell Notes Sample Chemical Symbol Density g/cm3 Physical Attribute Lead Pb 11.3 Heaviest Mass Copper Cu 8.9 Orange Iron Fe 7.9 Magnetic/Rusts Brass Cu & Zn 8.6 Yellow Aluminum Al 2.7 Lightest Mass Zinc Zn 7.1 Dull Gray

15. Comparing Volume, Density & Mass THINK about the concepts of VOLUME , DENSITY and MASS . Circle same or different . Explain WHY.

16. Comparing Volume, Density & Mass THINK about the concepts of VOLUME , DENSITY and MASS . Circle same or different . Explain WHY. #5. Objects A and B have the same or different densities because Iron Iron A B They are the same substance & the particles are packed the same way

17. Density Problems Identify the type of numbers you have. (unit labels) Understand what the problem is asking. It is a one step problem or two step problem ? Which formula should you use?

18. The following formulas are for finding different variables in density problems. Density Formulas m m v D = = = D v x m D v

19. Introduction to Density + Problems due tomorrow.