1. Energy and Changes in Matter
Energy is always involved when physical or chemical changes occur.
Energy can be in various forms.
heat
light
sound
Energy can be absorbed or released in a change, it is not destroyed or created.
law of conservation of energy

2. Law of Conservation of Mass and Energy
Mass and energy can be changed from one to the other, but the total amount remains constant.

3. Classifying Matter

4. Classification of Matter
A mixture is a blend of two or more kinds of matter, each of which retains its own identity and properties.
mixed together physically
can usually be separated
Homogeneous mixtures are called solutions
uniform in composition (salt-water solution)
Heterogeneous mixtures
not uniform throughout (clay-water mixture)

5. Homogeneous
Heterogeneous

6. Pure Substances A pure substance has a fixed composition.
A pure substance differs from a mixture in the following ways:
Every sample of a given pure substance has exactly the same properties.
Every sample of a given pure substance has exactly the same composition.
i.e. Water is always 11.2% hydrogen and 88.8% oxygen.
Pure substances are either compounds or elements.
Compounds
Can be broken down by chemical means
Elements
Can’t be broken down by chemical means

7. Separation of a Mixture
Filtration
Used for the separation of solids from fluids (liquids or gases) by interjecting a medium to fluid flow through which the fluid can pass, but the solids (or at least part of the solids) in the fluid are retained.
An analogy which is sometimes useful is to suppose a mixture of bees and wasps passing over a flower bed. The bees would be more attracted to the flowers than the wasps, and would become separated from them. If one were to observe at a point past the flower bed, the wasps would pass first, followed by the bees. In this analogy, the bees and wasps represent the analytes to be separated, the flowers represent the stationary phase, and the mobile phase could be thought of as the air.

8. Separation of a Mixture
Chromatography is a laboratory technique which involves passing a mixture dissolved in a "mobile phase" through a “stationary phase,” which separates the components of the mixture.
The components of dyes such as ink may be separated by paper chromatography.
The key to the separation is the differing affinities among components, stationary phase, and mobile phase.
An analogy which is sometimes useful is to suppose a mixture of bees and wasps passing over a flower bed. The bees would be more attracted to the flowers than the wasps, and would become separated from them. If one were to observe at a point past the flower bed, the wasps would pass first, followed by the bees. In this analogy, the bees and wasps represent the analytes to be separated, the flowers represent the stationary phase, and the mobile phase could be thought of as the air.

9. Stationary Phase
Mobil Phase

10. Separation of a Mixture
Distillation
Process of separating compounds utilizing the differences in the compounds boiling points.
When the mixture is heated, the compound with the lowest boiling point will evaporate first.
The vapor is collected in a separate container.

11. Separation of a Mixture
Distillation A B

12. Separation of a Mixture
Fractional Crystallization is
a method of refining substances based on differences in solubility
If two or more substances are dissolved in a solvent, they will crystallize out of solution (precipitate) at different rates.
This technique is often used in chemical engineering to obtain very pure substances, or to recover sellable products from waste solutions.

13. Introduction to the Periodic Table
The vertical columns of the periodic table are called groups, or families.
Each group contains elements with similar chemical properties.
The horizontal rows of elements in the periodic table are called periods.
Physical and chemical properties change somewhat regularly across a period.
The closer two elements are to one another, the more similar their properties.

14. (Atomic Mass)

15. Metals The Periodic Table Nonmetals Metalloids Period Group
Properties vary
Total of 7 periods
The Periodic Table
Group
Have similar properties
Total of 18 groups
Nonmetals
Metals
Group or family
Metalloids
Period

16. Types of Elements
Metals
A metal is an element that is a good electrical conductor and a good heat conductor.
Properties of metals
most are solids at room temperature
malleable - they can be hammered or rolled into thin sheets
ductile - they can be drawn into a fine wire
conduct electricity and heat well
luster - shiny when polished

17. Types of Elements
Nonmetals
A nonmetal is an element that is a poor conductor of heat and electricity.
Properties of nonmetals
many are gases
solids are brittle
poor conductors of heat and electricity
Carbon, the graphite in “pencil lead” is a great example of a nonmetallic element.

18. Properties of metalloids all metalloids are solids at room temperature
Metalloids straddle the border between metals and nonmetals on the periodic table.
Types of Elements
Metalloids
A metalloid is an element that has some characteristics of metals and some characteristics of nonmetals.
Properties of metalloids
all metalloids are solids at room temperature
semiconductors of electricity

19. Noble Gases – Group 18 Elements
Unreactive
Gases at room temperature
Neon, argon, krypton and xenon are used in lighting
Helium is used in balloons