9/03/13

1. 15 16 Atomic Theory Atomic Theory 9/03/13 9/03/13 Application: Fold and Glue notes here when done Starter: Match on next slide Connection: Paste Chart Here Practice: Atom 2.Electron Cloud Exit: Pick an atomic theorist, If they were alive today, what would you ask them?

2. Match the equipment with its correct use Apron Fire Blanket C. Goggles D. Gloves E. Eye Wash 3 • 1. Use when heat is present or harmful chemicals to the skin are being used • 2. Use to flush your eyes if you get any glass and/or chemicals in your eye for at least 5 minutes • 3. Always wear when dealing with harmful chemicals or hazardous materials • 4. Use to smother a fire by throwing it over the fire and patting the fire out • 5. Always wear when any chemicals, glass containers, or heat is being used 4 5 1 2

3. Agenda • 1. Starter • 2. Practice • 3. Notes • 4. Connection • 5.Exit

4. Table of Contents Date Lecture/ Activity/ Lab Page 8/28/ Syllabus /Notebook Guidelines 1-2 8/28 Periodic Table/ Formula 3-4 8/28 Tools/ Measurement 5-6 8/28 Lab Report/ Investigations 7-8 8/28 Restroom passes/Homework Log 9-10 8/29 Safety equipment 11-12 8/30 Atoms Vocabulary 13-14 9/3 Atomic Theory Research notes 15-16

5. Practice • Define: Atom 2.Electron Cloud

6. Application: Atomic Theory Draw this chart on your Notebook paper; will glue afterward Exit

7. The History of the Atom

8. The Beginning of the Atom

9. Early Models of the AtomDemocritus460 BC- 370 BC • Universe was made of empty space and tiny bits of stuff • Called these tiny bits of stuff atomos • Atoms could not be divided

10. Early Models of the AtomDaltonEarly 1800’s • All elements are composed of indivisible particles. • Atoms of the same element are the same • Atoms of different elements are different. • Compounds consisted of atoms of different elements combined together

11. Dalton’s Model of the Atom He believed the atom was a solid sphere An analogy to his atom would be…

12. Early Models of the AtomThomson1906 • Plum pudding model • Atom made of a positively charged material with the negatively charged electrons scattered through it.

13. Plum Pudding is an English dish sort of like bread pudding with raisins in it. An American analogy to his atom would be… …Is like… But we’ll still refer to it as the “Plum Pudding” model in class

14. Early Models of the AtomRutherford 1909 • Mostly empty space • Small, positive nucleus • Contained protons • Negative electrons scattered around the outside

15. Example of Rutherford’s Atom

17. Early Models of the AtomBohr1913 • Electrons move in definite orbits around the nucleus

18. Lewis Dot Structure1916 • Recognized that not all electrons in an atom play a role in chemical bonding • The outermost electrons of an atom, called the valence electrons are chemically important.

19. Erwin Shrodinger • 1924 - Austrian physicist; developed the electron cloud model Electron Cloud Model Proposed by Erwin Schrodinger

20. Erwin Shrodinger • His Theory: • The exact path of electrons cannot be predicted. • The region referred to as the electron cloud, is an area where electrons can likely be found.

21. James Chadwick • 1932 - English physicist; discovered neutrons • His Theory: • Neutrons have no electrical charge. • Neutrons have a mass nearly equal to the mass of a proton. • Unit of measurement for subatomic particles is the atomic mass unit (amu).

22. Modern Model of the AtomThe electron cloud1920’s • Sometimes called the wave model • Spherical cloud of varying density • Varying density shows where an electron is more or less likely to be

23. Connection:Check which of these applies to each Theorist

24. Exit • Pick an atomic theorist. If they were alive today, what would you ask them?