1. Atomic structure and the Periodic Table

2. Notes: Write down important vocabulary words as we go through today’s Power Point.

3. Element song

4. Review: Subatomic Particles as listed in a block on the period table.

5. Proton: p +, positively charged particle, in nucleus. Neutron: n o, no charge, in nucleus. Electron: e -, negatively charged particle, in electron levels, filled by lowest energy levels first with a max pair in each energy level.

6. Atomic number = the number of protons. Average Atomic mass = the number of protons plus the average number of neutrons in the nucleus.

8. Isotopes – atoms of an element with differing amounts of neutrons The average atomic mass is the average mass of a mixture of isotopes that occur in nature.

9. Ions – atoms of an element with differing amounts of electrons. If electrons do not equal protons, we call it an ion, not an atom. Ions will have a positive or negative charge. Do not confuse ions and isotopes. Ions –different amounts of electrons.

10. An atom has no charge so there is an equal number of electrons and protons. Remember that the mass is the total number of neutrons and protons.

11. Bohr Modeling: Bohr Models are one of the most used models. Even though the orbit shapes are not correct, the model is very useful and explains most chemical behavior.

12. Bohr Models

13. The Bohr Model of the Atom One of the simplest working models of the atom is that developed by Niels Bohr. In this, a central nucleus containing protons and neutrons is orbited by electrons. The electrons are arranged in shells or energy levels.

14. Bohr Model: 1. Nucleus in the center with protons and neutrons. 2. Electrons in different orbit levels. 3. Larger Orbits represent electrons with more energy.

15. Electrons in shells nearer the nucleus have lower energy than those farther away.

16. Today’s model of an atom is a dense positively charged nucleus surrounded by a negative cloud of electrons and is based on probability

17. Electron cloud - the region around the nucleus of an atom with a 90% or high probability of finding an electron

20. http://www.orbitals.com/orb/orbtable.htm

21. Periods – there is a period for each electron level. 1 st electron level only has 2 atoms. 2 nd electron level only has 8 atoms. 3 rd electron level has 18 atoms. 1s 1 2s 2 2p 6 3s 2 3s 6 3d 10 1s 2

22. Groups or Families: Up and Down Have Similar Properties. Look at back of book, on top of Group for group name. Left side is group 1 or 1A. US uses number 1, Europe uses 1A. Right side is group 18.

23. Left Group 1 is called Alkali Metals. Left 2 nd Group 2 is Alkaline Earth Metals. Rightmost Group 18 is Noble Gases.

24. Electron Dot Structure

25. Electron dot structure = represent the electrons in the outermost shell

26. Never more then 8 dots, these dots will allow us to predict how the element reacts

27. How many dots would go around these atoms? Cl Li Na Mg C