1. DENSITY

2. What is Density? Density is a property of all matter.
It is used to identify all pure forms of matter.

3. Formula Density = Mass / Volume D = m / v
Units for Density: g/cm3 or g/mL

4. What does Density Compare?
Density compares the mass of a given amount of matter and the space it takes up (volume).
This relationship is unique to every pure form of matter.

5. Sample Problem
A metal block has a mass of 140 g and a measured volume of
75 cm³. What would the density of this metal block be?
D = m / v
140 g / 75 cm3
D = g/cm³
FORMULA
SETUP
FINAL ANSWER
D = 1.9 g/cm³

6. Density is a CONSTANT
Density is a constant and does not depend on the amount of the substance.

7. What does Constant mean?
A constant is when a quantity will always be the same, no matter what (Intrinsic property).
For example:
Boiling Point
Melting Point

8. Density Comparisons
If possible, density is a property that causes matter to layer itself.
The lower density objects will rise above more dense forms of matter.
This is important to remember!!

9. Remember the Density of Water
When determining the density of an object, it is important to know what the density of water is.
No matter what, the density of pure water is
1.0 g/cm³.
This value will be used to determine if an object will sink or float when it is placed in water.

10. Float/Suspend/Sink
An object will do three things when placed in water.
Float
Suspend
Sink
An object will float in water if Density < 1.0 g/cm³
An object will “suspend” in water if Density = 1.0 g/cm³
An object will sink in water if Density > 1.0 g/cm³

11. Sinking Objects
Any object with a Density > 1.0 g/cm³, will sink to the bottom in water.
The more dense an object is, the quicker it will sink!!

12. Floating Objects
Any object with a Density < 1.0 g/cm³, will float at different levels.
The density of an object will determine what % of an object is directly below water level.
For example:
If the density of an object is 0.5 g/cm³, then 50% of the object is below water level.
If the density of an object is 0.7 g/cm³, then 70% of the object is below water level.
If the density of the object is 1.0 g/cm³, then the object will not touch the top or bottom of the water.

13. Any Questions?

14. Now… for a little

15. THE EQUATION
D =M V
ass
ensity
olume

16. "Mountains over
deserts and valleys"
THE TRICK M D V

17. Cover up the one you want to solve for!M D V

18. Let’s solve for VOLUME.
“M over D” is remaining so we divide! M D V

19. Let’s solve for Density.
“M over V” is remaining so we divide! M D V

20. Let’s solve for Mass. M D V x
“D next to V” is remaining so we multiply! M D V x