1. Density of Fluids
Properties of Matter

2. Density of Fluids Key concepts:
How does the density of a material change as the temperature changes?
Fluids – liquids and gases
Mass remains the same from solid to liquid to gas, but volume changes.

3. Density of Fluids What is a fluid? Measuring density of a liquid m D V
Any matter that has the ability to flow
Liquids, gases
Measuring density of a liquid
The method remains the same:
D=m/v
Units: g/mL m D V

4. Density of Fluids The volume of liquid silver
The mass remains the same as when it was solid
The volume has changed!
When it was a solid, the atoms were in fixed positions
As a liquid, the atoms are moving more freely and farther apart, taking up more space

5. Density of Fluids
Compare the density of a solid to that substance as a liquid
If you increase the volume you will decrease the density
Solids will even change density as they are heated and cooled even before they melt due to the increased vibration of the molecules

6. Density of Fluids Water
Most materials are more dense as a solid than in their liquid state
Water is a notable exception – ice is less dense than liquid water!! It floats.
When water freezes, its crystal structure has a large amount of empty space, causing the volume to increase.

7. Density of Fluids
Imagine you are an aquatic animal (frog, fish, turtle, etc). Describe how life would be different if ice were more dense than water.