Properties%20of%20Matter

1
Properties of Matter

• Questions lecture covers on test
• 1, 2, 3, 4, 13, 14, 15, 16, 30

2

• Intensive Properties-Do NOT change if you change
  the amount of substance
• Example softness, hardness, boiling point,
  melting point, hair color brown
• Extensive Properties-Change as you change the
  amount of a substance example mass, volume,
  length, hair short

3
Physical Properties of Matter

1. Buoyancy
2. Density
3. Viscosity
4. Hardness
5. Brittleness
6. Elasticity
7. Malleability
8. Conductivity
9. Solubility
10. Tensile Strength

4
1. Density

• The compactness. It describes how tightly atoms
  are packed.
• The relationship of
• mass to volume
• Density
• mass / volume

5
Buoyancy

• The measure of the upward pressure a fluid exerts
  on an object
• Buoyant force on an object mass of the
  displaced fluid
• will float if buoyant force gt object mass
• will sink if buoyant force lt object mass
• Shape affects buoyancy
• steel rod will sink in water
• A sheet of steel (like a boat) displaces more
  water

6
Buoyancy and Flash Flooding

• For each foot the water rises up the side of the
  car, the car displaces 1,500 lbs. of water.  In
  effect, the car weights 1,500 lbs. less for each
  foot the water rises.
• The buoyancy of two feet of water will float most
  cars, allowing current to carry them away

7
Viscosity

• Measure of a materials resistance to flow
• Viscous fluids are thick and hard to pour
• Determined by shape and size of molecules
• Large, bumpy molecules create
• more friction as they slide past
• flow more slowly (MORE VISCOUS)
• Small, smooth molecules flow
• more quickly (LESS VISCOUS)

8
Hardness

• Measures a solids ability to resist scratching
• Hard substances can scratch
• softer substances
• Ex. Diamonds are the hardest
• natural substance on Earth
• Does NOT mean rigid!

9
Brittleness

• Measures a materials tendency to shatter on
  impact (or to break without bending)
• Ex. Glass shatters in car accidents
• Now glass is made with a
• shatter-proof coating that
• holds the shards together
• when glass breaks

10
6. Elasticity

• Measures a solids ability to be stretched and
  return to its original size
• Gives objects the ability to bounce and withstand
  impact without breaking

11
7. Malleability

• A solids ability to be pounded into thin sheets
• Metals are very malleable (gold jewelry)

12
8. Conductivity

• The ability of a material to conduct
• Electric current
• Heat
• Sound

13
9. Tensile Strength

• A measure of how much pulling, or tension, a
  material can stand before it breaks
• Important property of fibers
• Ex Spider silk fibers have more than 5 times
  the tensile strength of steel!

14
Chemical Properties

• Reactivity
• Flammability

15
Triple Beam Balance

• Carry from base
• Estimate the hundreths place
• 1.23

16
Graduated Cylinder

• More precise than a beaker
• Accuracy-the degree of closeness to the actual
  value
• Precision-repeatable you get the same value each
  time

17
Accuracy vs. Precision

• High __________ low __________
• Accuracy
• Precision

18
Accuracy vs. Precision

• High ___________ Low ________
• Precision
• Accuracy

19

• Why do you think the can of Coke sank and the can
  of Diet Coke floated?
• What can you say about the density of the can of
  Coke compared to the can of Diet Coke?
• What can you say about the density of the can of
  Diet Coke compared to water?
• What is the density of water?
• How can we calculate the density of the cans of
  Coke and Diet Coke?

20
In your journal collect Data

• Mass of Coke___________
• Volume of Coke___________
• Density of Coke_______________
• Mass of Diet Coke
• Volume of Diet Coke
• Density of Diet Coke