1. Where are more people per space, NYC or the Smokie Mountains?

2. DENSITY
MAP 3.1 Population density in 2000 from GPWv3 adjusted to UN totals

3. What two values must be determined to calculate density?
MASS
VOLUME

4. MASS Amount of matter (particles) in an object. Instrument: balance
Units: grams (g)
How is mass different from weight?
Weight accounts for gravity AND
Gravity depends on the mass and distance of the two objects.

5. Volume The space an object occupies
Instrument: ruler or graduated cylinder
Units: centimeter cubed (cm3) or milliliter (mL)

6. Volume Cubic solid Equation Irregular solid Displacement method
Length x width x height
Irregular solid
Displacement method
Volume of a cylinder?
Volume of liquid?
How is area different from volume?

7. Density of materials

8. COMMON MATERIALS
Water ………………………1.00 Glass………………………2.60
Granite…………………… Bone……………………….1.85
Human Body……………… Butter……………………
Ice………………………… Carbon…………………….2.60
Kerosene…………………… Chalk………………………2.36
Salt………………………… Coal………………………..1.50
Sand………………………… Cork………………………..0.25
Sulfuric Acid……………… Gasoline……………………0.72
COMMON METALS
Aluminum………………… Mercury……………………13.60
Brass……………………… Nickel………………………8.80
Chromium………………… Platinum……………………21.50
Copper………………………8.63 Silver……………………….10.40
Gold………………………… Tin………………………….7.30
Iron………………………… Uranium……………………18.70
Lead………………………… Zinc…………………………6.90
Magnesium………………….1.74
SOME COMMON WOODS
Alder………………………0.40 White Pine…………………0.43
Ash……………………… Maple………………………0.69
Balsa………………………0.12 Oak…………………………0.85
Douglass fir……………… Yellow Pine………………
Ebony…………………… Walnut……………………..0.67
Larch (tamarack)………..0.51
Apples

9. Density DENSITY = mass volume
Density is one of the best physical properties for determining what material it is!
Regardless of size or shape, for a uniform material, density does not change at constant temperature and pressure.
example: A brick of gold or a small nugget of gold might have different masses and volumes but the density does not change!

10. M V D Density Triangle DIVIDE Multiply Example#1
Mass= 25g, volume =5mL
Example#2
Density =5 g/mL
Volume= 10 mL M
mass
DIVIDE
Density = 5 g/mL
Mass= 10 g
Multiply V D
Volume
Density
So, d=m/v and v=m/d and m=d x v

11. Density facts
Most materials are most dense in the solid phase. But water is most dense in the liquid phase.
If you increase the temperature of a material, the mass stays constant, the volume increases, and the density decreases.
Increase the pressure on a material and the mass stays constant, the volume decreases, and the density increases.

12.                                                                                                                    
Figure 3. Relationship of water temperature to density for distilled water

14. Steps in Determining DENSITY OF A LIQUID
Find the mass(in grams) of an EMPTY graduated
cylinder using electronic scale.
2. Pour an amount of the sample liquid into the same
graduated cylinder.
Find the mass(in grams) of the graduated cylinder
AND the liquid TOGETHER.
4. SUBTRACT to find the mass of the liquid ALONE.
Read the volume of the liquid (in mL) in the graduated cylinder.
6. Put the values into the density formula:
Density = ________g =
mL _________g/mL