11/13/08
Post date: Nov 13, 2008 1:12:14 PM
Bell Activity: Give a complete description of the machine on the green table.
Physical properties
Characteristics that can be observed without changing the identity of the substance
Help identify a substance
Can be observed or measured
Color
Melting point
Boiling point
Strength
Hardness
Magnetism
Conductivity
Density
Help determine uses for a substance
Density
Is mass / volume
Is a physical property
Is constant for a given substance
Can be used to identify a material
Is DIFFERENT FROM WEIGHT!!!!!
People use "light" and "heavy" for weight and for density
Many would say a brick sinks in water because it is "heavy" -- actually, it is because the brick is more dense than water. A boat, which is much "heavier" than a brick, will float in water because it is less dense than water.
M&M density activity
Density Lab due Monday (lab can be found in "handouts" section)