1.  Grab your notebook  Pick a partner and grab these supplies: ◦ 4 pieces of white paper (for the pair) ◦ 4 colored pencils (preferably red, blue, green, and black) (each) ◦ 1 pair of scissors  Make sure you have a pen or pencil out, ready to go!

3.  What does an atom look like? (Sketch a picture)  What do you know about atoms?

4. How have scientists described atoms?

5. 400 BC Democritus *Elements made of tiny particles that couldn’t be split. *Atomos = uncuttable

6. 1904 Thomson *Atoms had negative particles *Like chocolate chips in cookie dough

7. 1911 Rutherford *Mass of atom & all positive (+) charges were found in a central nucleus

8. 1913 Bohr *Electrons orbited the nucleus *Nucleus = protons + neutrons (+) (0)

9. Current Electron Cloud Model *Electrons have no particular orbit, but occur in certain areas more often.

10.  Grab your notebook and textbook  Pick up these supplies: ◦ 5 colored pencils (preferably red, blue, green, black, and purple)  If you used different colors yesterday, grab those instead.  Make sure you have a pen or pencil out, ready to go!

11.  Atoms have 3 major parts: ◦ Proton (+) ◦ Neutron (0) ◦ Electron (-)

12. THREE SUBATOMIC PARTICLES ParticleSize Electric Charge Effect of Adding or Removing PROTON“Big”+1 Changes the element into another element. ELECTRON“Small” The element stays the same, but its electric charge changes. NEUTRON“Big”0 Changes the weight (not the element), making it more or less stable.

13.  First fold in ½ the long way.  Now fold in ½ the short way.  Tape into your notes!

14.  Very tiny particles  Different combinations produce neutrons and protons.  Studied by smashing together charged particles

15.  Imagine the Superdome or Memorial Stadium.  Put 1 marble on the 50 yard line. That is the nucleus.  All of the other space is the electron cloud.  REMEMBER: 500,000 atoms fit behind 1 human hair!

17.  Pick up notebook and textbook  Open to page 549

19.  Turn to page 549 and read the section on “The Electron Cloud Model”  In your own words, describe what the electron cloud is like. (Where would I find electrons? How big is it? Etc.)

20.  What 2 atomic particles make up most of the atomic mass?  What are some ways elements are grouped?

21. Carbon 6 C 12.011 Atomic Number Symbol Mass Number

22.  Symbols: 1 to 3 letters that represent a specific element  1 st letter is capitalized, rest are lower-case  Examples: ◦ C = CarbonHe = Helium ◦ H = HydrogenLi = Lithium ◦ O = Oxygen

23.  Sometimes the letters don’t seem to make sense. Some elements are called by their Latin names or other features. ◦ Examples:  Ag = Silver (Argentum)  Na = Sodium  K = Potassium  Au = Gold

24.  Atomic Number: Equal to the number of protons (+) ◦ Examples:  H = 1  C = 6  O = 8

25.  Mass Number: ◦ Unit of measurement = amu (atomic mass unit)  1 proton = 1 amu  1 neutron = 1 amu  1 electron = 0 amu (too light to count)  Reminder: Round to the closest whole number

26. MASS NUMBER = PROTONS + NEUTRONS or NEUTRONS = MASS NUMBER – ATOMIC NUMBER Example: How many neutrons are in U-236? Neutrons = 236 – 92 = 144 neutrons

27.  Sometimes elements have different masses.  Isotope: an element with different numbers of neutrons ◦ Sometimes this makes them radioactive ◦ Example: Carbon-12 is most common, but we use carbon-14 to date objects ◦ C-12 = 6 protonsC-14 = 6 protons 6 neutrons 8 neutrons

28.  ORAL ASSESSMENT  How many neutrons would we need?  Where would I place the electrons?  How many electrons would I need?

29.  1. Sketch what your “hardware” periodic table looks like.  2. What are the characteristics you used to make rows and columns?  3. How do you think this is related to the chemical periodic table?

30.  Grab your notebook and book  Pick up: ◦ 3 colored pencils  Green, yellow, and blue (make sure they aren’t too dark) ◦ 2 periodic tables  One filled out and one blank

31.  Energy levels closer to the nucleus have less energy.

33.  Numbered 1 to 7  All stable elements have 8 electrons in the outer level.

34.  Energy levels are like stairs.  The numbers of electrons that can be held in an energy level is 2n 2 for each step. (n=level #)

35. Nucleus Energy Level 1 2 electrons Energy Level 2 8 electrons Energy Level 3 18 electrons

36.  Electron dot diagrams use the symbol of the element and dots to represent electrons.

38. Metals Non- metals Metalloids

39.  From left to right  As you go to the right, you add 1 proton and 1 electron.  The row ends when there are 8 electrons in the outer energy level

40.  Up and down; columns  Elements in the same group have similar properties (have same # of electrons).  Group 1, very reactive (only 1 electron)  Group 8A, not very reactive (has all 8 electrons)

41.  Grab 5 different colored pencils (doesn’t matter which colors  You’ll also need your book, notebook, and yellow homework sheet from yesterday!

42.  Only 1 electron in the outer energy level  Very unstable, wants to get rid of the electron  Reacts with Halogens (Group 7A) best  Has metallic properties  Examples: Li, Na, K

43.  2 electrons in the outer energy level  Like to get rid of those electrons (but not as much as Group 1A)  Has metallic properties  Examples: Be, Mg, Ca

44.  7 electrons in their outer shell  Want to “steal” 1 electron from other atoms  Very reactive with Groups 1A and 2A  Have many different properties (solid, liquid, and gas)  Examples: F, Cl, Br

45.  Have a full outer shell of 8 electrons (except He, which has 2)  Do not react with many other chemicals because they are very stable  Properties: All gases at room temp  Examples: He, Ne, Ar

46.  Located between metals and non-metals  Have properties of both depending on what they are reacting with  Examples: B, Si, As

47.  1. Checking Understanding Quiz ◦ You WILL be able to use a periodic table.  2. When you finish the quiz, find a partner (group of 3 MAX) and go over your yellow sheet homework sheet from last week together. (A key is on my desk if you need it.) Turn the sheet in when you are done.  3. Start on your homework assignment ( DUE tomorrow!!) ◦ Pg. 549 1-4; pg. 553 1-2; pg. 562 1-3; pg. 570 3-6, 10, 18 ◦ Can be written on a BLANK left hand page in your notebook or on loose-leaf notebook paper.

48.  School Poll ◦ You will take turns using the computers to take this short online survey. ◦ MAKE SURE TO TURN IN YOUR ENVELOPES!!  Review Sheet ◦ Spend time filling our your review sheet.  Rest of the week: ◦ Tomorrow: Class review ◦ Thursday: Test  Grades are due early next week…make sure you get your work in!