1. Introducing Chemistry
Chapter 2 - Matter and Change

2. What is Chemistry?
Chemistry - Defined as the study of composition, structure, and properties of matter
Matter -
Has mass
Takes up space
Exists in four states: solid, liquid, gas, plasma

3. Is it matter??? Rocks Smoke Bacteria Baby powder Salt Oxygen stars
Milk
Mars
Gravity
Air
Jupiter
Magnetic force
Light
Steam
Dissolved sugar
Dust
Rotten apples
Love
Electricity
Heat
Cells
Sound waves
Atoms
Water
Fire

4. Chemistry cont.
Chemical – any substance that has a definite composition.
Ex.) Nitrogen, Oxygen, Water, Hydrochloric acid

5. Classification of Matter
1. Pure substance
*fixed composition
*all samples have identical properties
*2 kinds of pure substances
1. Elements (one type of atom)
2. Compounds (two or more types of atoms)
Atom – the smallest unit of an element

6. Compound or Element?

7. Classification of Matter, cont.
2. Mixture
*Blend of 2 or more kinds of matter
*Each part retains its unique properties
A. Homogeneous (uniform)
- also called solutions
B. Heterogeneous (not uniform)

9. Properties of Matter
Physical Property *Property that can be observed/measured without altering the substance’s composition ex/ melting point, color, density Chemical Property *Property that relates to a substance’s ability to change into new/different substances ex/ability of iron to rust

10. Properties of Matter, cont.
Extensive properties – depends on amount of matter, not type ex/ calories, mass, length Intensive properties – depends on type of matter, not amount ex/ density, melting point, boiling point

11. Changes in Matter
1. Physical Change *Changing matter without changing its chemical identity ex/ tear paper, phase change 2. Chemical Change (Chemical reaction) *Changing matter into a new substance *Atoms are rearranged, NOT created ex/ Fe + O2  Fe2O3

12. Physical Change - States of Matter
Gases
-Indefinite shape
-Indefinite volume, compressible
Liquids
-Indefinite shape
-Definite volume, slightly compressible
Solids
-Definite shape
-Definite volume, incompressible
Plasma

13. Physical change – Phase changes
Solid  liquid
Liquid  gas
Gas  liquid
Liquid  solid
Gas  solid
Solid  gas
Melting
Vaporization
Condensation
Freezing
Deposition
Sublimation

15. Chemical Change
Chemical reaction – The final substances are chemically different from beginning substances.
Reactants – substances that begin and react
Products – the resulting chemicals

16. Evidence of a Chemical Change
Color Change
Odor
Gas evolved
Energy produced
Precipitate formation

17. Branches of Chemistry
Organic Chemistry – the study of most carbon-containing compounds
Inorganic Chemistry – the study of non-organic compounds particularily metals
Physical Chemistry – the study of the properties and changes of matter and their relation to energy

18. Branches of Chemistry
Analytical Chemistry – the identification of the components and composition of materials
Biochemistry – the study of substances and processes of living things
Theoretical chemistry – uses math and computer to understand the principles behind chemical behavior and predict properties of new compounds

19. Chapter 1 Review
Pg. 22 ~ 1, 3, 6-14, 17, 19-21