1. MATTER Matter is anything that has MASS & VOLUME.
Mass = the amount of matter an object contains
Measured in grams (g)
Volume = the amount of space an object takes up
Measured in milliliters (mL) or centimeters cubed (cm3)
There are three main states of matter. We determine the type of matter by its physical properties.

2. Classifying Matter
Substance (pure): made up of only one kind of matter; every particle has the same fixed composition and properties
a. Elements
Smallest unit: atom
Symbol: Au, Na, He, N
b. Compounds: a substance that contains two or more elements chemically combined in a fixed proportion.
Smallest unit: molecule
Formula: C6H12O6, H2O
Compounds can be broken down into simpler substances by chemical means. Elements cannot.
The properties of a compound are different from the properties of the elements from which it was created – e.g. NaCl

3. Classifying Matter
2. Mixture: physical blend of two or more components.
Example: salt-sand mixture
The basic identity of each substance is not changed.
Properties are not the same throughout.
Composition is not fixed.
Can be separated into its components by physical processes.

4. Heterogeneous: composition is not uniform throughout.
Types of Mixtures
Heterogeneous: composition is not uniform throughout.
Often components are large enough to be seen.
Example: Pizza
Homogeneous: constant composition throughout, but the amount of each substance can vary.
Examples: sugar water, vinegar
Solutions: liquid or gaseous mixtures
Alloys: solid solutions of metals
Examples: steel, brass, bronze

5. Label as Substance or Mixture: If Substance, Element or Compound
Label as Substance or Mixture: If Substance, Element or Compound? If Mixture, Hetero- or Homogeneous?
1. Salt water
2. vinegar
3. sugar
4. sodium
5. gasoline
6. bronze
7. orange juice & pulp
8. blood
9. baking soda
10. ethanol
11. vitamin C
12. hamburger
13. aluminum foil
14. iron
15. air
16. carbonated beverage
17. steel
18. sand and water
19. milk
20. dirt
21. table salt
22. lemonade

6. Physical Properties
Physical Property: a characteristic of a substance that can be observed or measured without changing the substance’s composition.
Examples: color, density, electrical conductivity, and physical state (solid, liquid, gas), solubility, freezing/melting point, boiling point, volatile
Density: amount of matter (mass) contained in a unit of volume (density = mass/volume; [g/mL])
Solubility: the ability of one substance to dissolve in another.
Volatile: describes substances that change to a gas easily at room temperature (ex. alcohol, gasoline)

7. You identify substances by their physical properties all the time.
Extensive properties - Depends on the amount of matter in a sample.
Ex. Mass, volume, length, etc.
Intensive properties - an intensive property depends on the type of matter present.
Ex. Color, luster, malleability, taste, reactivity.
You identify substances by their physical properties all the time.

8. Physical Change
Physical Change: a change in matter that does not involve a change in the identity of individual substances.
Dissolving
Changes in state

9. Chemical Properties
Chemical Properties: the ability of a substance to react with other substances or to decompose.
To determine the chemical properties of a substance, the substance must be allowed to react with other substances and therefore its composition will be changed.
Examples:
iron combines with oxygen at room temperature to produce rust
sodium reacts explosively with water

10. Chemical Change
Chemical Change (Chemical Reaction): the change of one or more substances into new substances.
REACTANTS  PRODUCTS
Involves the rearrangement of atoms.
Law of Conservation of Mass: no atoms are created or destroyed during a chemical reaction.
Mass of Reactants = Mass of Products

11. Label as a “physical” or “chemical” change.
change in shape
tarnish
- physical
– chemical
rusting of iron
grind
- chemical
Physical
explode
melt
cutting a sheet of paper
boil
– physical
breaking a crystal
ferment
corrode
salt dissolving in water
Bend
Oxidize
Burn
- chemical
condense
- physical
vaporize
Rot
Freeze
decompose

12. Recognizing Chemical Changes
Transfer of Energy -- Heat or Light is released or absorbed.
Change in Color (drastic)
Production of a Gas (excluding changes in physical state and dissolved gases – e.g. opening a carbonated soda)
Formation of a Precipitate (a solid that forms and settles out of a liquid mixture – e.g. soap scum)

13. STATES OF MATTER & THEIR PROPERTIES
What’s the ‘matter’ with you?

14. Solids Definite shape and volume
Will not move (static) to fit container
Will not flow
Particles are together
Low kinetic energy
Low entropy - Entropy change has often been defined as a change to a more disordered state

15. Liquids Indefinite shape, definite volume. Will move to fit container
Will flow.
In most cases particles are more spread out
Particles have higher KE
Particles have higher entropy

16. Gases Indefinite shape, indefinite volume. Will move to fit container
Will flow.
Particles are spaced wide apart.
Very high KE
High entropy (chaotic, disordered)

17. Plasma Electrically charged gas. Will flow High KE High Entropy
Ex. lightning

18. Physical Change
When matter changes from solid to liquid or from liquid to solid, it is changing its physical state, therefore it is a physical change or phase change.

19. PHASE CHANGES MELTING FREEZING VAPORIZATION (boiling) CONDENSATION
Solid  Liquid
Liquid  Solid
Liquid  Gas
Gas  Liquid
Solid  Gas
Gas  Solid
MELTING
FREEZING
VAPORIZATION (boiling)
CONDENSATION
SUBLIMATION
DEPOSITION

20. MELTING POINT AND BOILING POINT
Melting Point = MP
Boiling Point = BP
Example:
Aluminum
Melting Point = 660 oC
Boiling Point = 2519 oC
When would aluminum be considered a liquid?
At what temperature would aluminum freeze?
Between 660 & 2519 oC
660oC

21. Substance Melting Point (oC) Boiling Point (oC) Aluminum 660 2519
Methanol
-94 65
Chlorine
-101
-35
Oxygen
-218
-183
Sodium chloride
801
1413
Zinc
420
907
Below -94oC
When would methanol be in a solid state? _____
When would oxygen be in a liquid state? _____
When would sodium chloride be in a gas state? ______
Between -218oC and -183oC
Above 1413oC

22. PHASE DIAGRAM Pressure Temperature LIQUID PHASE SOLID PHASE GAS PHASEB
Pressure
SOLID PHASE
GAS
PHASE A
Temperature
A – triple point
B – critical point

23. PHASE DIAGRAMS
Triple Point: the temperature and pressure at which three phases of a substance can coexist.
Critical Point: critical temperature above which no amount of pressure can change the vapor into a liquid.
Lines: indicate T and P at which two phases exist in equilibrium

24. A phase diagram is unique for each substance

25. Phase Diagram
WATER:
MP = 0oC
BP = 100oC

26. What phase change occurs when carbon dioxide goes from B to A?
Normal MP and BP means at standard pressure.
Standard Pressure = 1 atm
What phase change occurs when carbon dioxide goes from B to A?
FREEZING

27. HEAT
When a substance is heated its temperature increases until it changes state. When it changes state all energy is absorbed and the particles are pushed further apart.
When a substance is cooled from liquid to solid heat (energy) is released and particles move closer together.

28. Phase Changes TEMPERATURE DOES NOT CHANGE DURING A PHASE CHANGE.
All energy is going into pulling particles farther apart (increasing potential energy).

29. A substance that evaporates easily has a higher vapor pressure.
Vapor Pressure: the pressure exerted by a vapor over a liquid in a closed container.
A liquid in a sealed container evaporates until its vapor pressure is high enough that the rates of evaporation and condensation are equal.
A substance that evaporates easily has a higher vapor pressure.
Add pic

30. Vapor Pressure Example
Ethanol is more volatile than water (evaporates more easily) and therefore has a higher vapor pressure. Ethanol vapors exert more pressure on its container at equilibrium.
Water molecules are more polar than ethanol molecules. Why do you think water has a lower vapor pressure compared to ethanol?

31. Vapor Pressure Concepts (cont’d)
Increasing the temperature of a liquid in a closed container increases the vapor pressure.
Boiling point: the temperature of a substance when its vapor pressure = atmospheric pressure.
Boiling point of a substance increases when the pressure on the liquid increases.

32. Thought Questions How does a pressure cooker work?
increased pressure increases boiling point
Why must foods cooked in boiling water at high altitudes be cooked longer?
lower pressure lowers boiling point
Why is a burn from steam at 100oC more severe than a burn from water at the same temperature?
gas has more potential energy.