1. States of Matter Density Buoyancy Viscosity NOTES!!!

2. What is Matter? Anything that has mass and takes up space
So pretty much anything you can imagine – from the air we breathe, to water we drink, to the sun and all the stars.

3. What are physical properties?
Watch and see!

4. DENSITY

5. Two Ways to Measure Matter..
Mass
Volume

6. Density is..
A property that relates mass and volume (combines them)
Density = mass/volume OR
Density equals mass per unit volume (g/cm3)

7. Density affects… Hardness (resistance to scratching)
Elasticity (ability to stretch and return)
Brittleness (likelihood to shatter)
Malleability (ability to made into thin sheets)
Tensile Strength (how much force before breaking)

8. Density of Fluids Tend to be less dense than solids
Molecules move around each other
Do not “stack” easily
Water is an exception – ice is less dense than water (due to structure of water)

9. Density Math
The density of a material can be determined by dividing the mass by the volume
Ex. What is the density of a 400 g block that has a volume of 16 cm3?
Answer: 400/16 = 25 g/cm3

10. Conversions Sometimes the mass is given in a unit other than grams.
Or the volume is given in a unit other than mL.
Ex. What is the density of a block that weighs 2.5 kilograms and has a volume of 40 cm3?
The mass must be converted into grams (g) so m= 2500g
Answer: 2500/40 = 62.5 g/cm3

11. Note…
A cm3 is equivalent to a mL. Specifically, mL is used for volume of gasses and liquids and cm3 is used for the volume of solids.

12. BUOYANCY

13. Definition
The measure of upward pressure a fluid exerts on an object

14. Buoyancy is… Determined by density Ruled by Archimedes’ Principle
The denser the fluid, the more buoyant force it applies
Ruled by Archimedes’ Principle
The force exerted on an object by a liquid is equal to the mass of the fluid displaced by that object

15. Displaced
To move something from its usual place

16. Therefore…
If buoyant force is greater than the mass of the object, the object FLOATS
If buoyant force is less than the mass of the object, the object SINKS

17. Neutral Buoyancy
Is achieved when the mass of the object is EQUAL to the mass of the liquid displaced by that object.
The object floats exactly in the position it is placed.

18. VISCOSITY

19. Definition
Measure of a material’s resistance to flow
(how hard it is to pour)

20. Viscosity is determined by…
Size of liquid molecules
Shape of liquid molecules
Temperature of liquid
Also applies to gasses

21. Therefore… A thick substance is described as being very viscous
Ketchup, syrup (cold)
Motor oils have different grades based on viscosity (10W-40, 10W-30)

22. Viscosity of Liquid
As temperature of a LIQUID increases, its viscosity decreases.
The additional kinetic energy allows the molecules to slide past each other with greater ease.

23. Temperature and gasses
As the temperature of a GAS increases, its viscosity increases.
Because gas molecules are far apart, they do not have to slide over each other very often in order to flow.
Raising the temperature actually increases the number of collisions between the molecules, resulting in an increase in friction and therefore, viscosity

24. Check it out!
Watch what happens!

25. 4 States of Matter
Solid
Liquid
Gas
Plasma

26. Solid State
Lowest energy form of matter
Molecules do not change position
Definite Shape
Definite Volume

27. Liquid State
Molecules can move around each other
Definite volume
Takes shape of container

28. Gas State
Molecules move freely and separate from one another
No definite shape
No definite volume

29. Plasma Most common state of matter (in universe)
Highest energy form of matter
Made up of ionized gas molecules (atoms breaking apart due to high heat/energy)