1. Physical Properties
Density

2. Changes of State: solid
Definite shape and volume
Do not expand or contract too much when heated or cooled.
Particles are held closely together by strong attractive forces

3. Changes of State: liquid
Take the shape of the container they are in, definite volume
Pressure is exerted equally in all directions
Held together by attractive forces
Particles are not so close together so they are more mobile

4. Changes of State: gas
No definite shape or volume, take shape and volume of the container they are in
Temperature and Pressure affect gases: dramatically alters them
Particles are very far apart, weak attractive forces between molecules allowing great mobility

5. density
Mass per unit volume of a material
Physics – kg/m3
Chemistry – g/mL or g/cm3
𝐷= 𝑚 𝑉
where D is density, m is mass and V is Volume
Note: the Greek letter ρ is used for density as well.

6. applications Density determines the use of an element
Aluminum (Al) is very light so is used for foil, aircrafts, boats, spacecraft, windmills, cars, tools, cans…

7. Calculations
Silver in a lab has a mass of 42.0 g and occupies a volume of cm3. Find the density of silver in this lab!
D = m/V
D = 42.0 g/4.00 cm3
D = 10.5 g/cm3

8. Numbers with units substituted in Answer rounded to match question
Marking system
Marks given for:
Formula stated
Numbers with units substituted in
Answer rounded to match question
Answer with units

9. Summary
YOU CAN IDENTIFY UNKNOWN MATERIALS BASED ON DENSITY, MELTING POINT, BOILING POINT, FREEZING POINT.
These are called Characteristic Physical Properties as they can be used to identify certain materials.

10. pg. 193 - define FP, MP, BP, read about Salt and Water
Class/home work
pg define FP, MP, BP, read about Salt and Water
pg. 198 #1-12. (use charts on page 193, 195)