1. Notes on the Periodic Table

2. Antoine Lavoisier  1790’s made a list of all the known elements; there were 23  By the 1870’s, there were 70 known elements  A system of organization was needed

3. Dimitri Medeleev https://encrypted- tbn1.gstatic.com/images?q=t bn:ANd9GcTzeKUuTTXAuY9m tgzBOeJXppe- olCc5lOuLAVqtgZBIZOuNKQA Was given credit for the first periodic table even though John Newland also developed an organizational system. Based on increasing atomic mass and similar chemical properties

4. Dimitri Medeleev https://encrypted- tbn0.gstatic.com/images?q=tbn:ANd9GcTdPYDxtXWpDpW W-T2xbDAILg8GYvV0SdyF3CIM3n7UMAT5370t9g Predicted the existence of unknown elements Some elements were out of order

5. Henry Mosely Measured the frequency of the X-rays given off by different elements. Each element gave a different frequency Frequency was mathematically related to the position of the element in the Periodic Table He could actually measure atomic number http://www.rsc.org/education/teachers/resources/periodictable/pre16/order/graphs.htm

6. Re- designed the periodic table to show an increase in atomic number. Periodic Table now follows the periodic law. Henry Mosely https://i.ytimg.com/vi/7QKA5kSu9To/m qdefault.jpg

7. Parts of the Periodic Table Metals Non-Metals https://encrypted- tbn2.gstatic.com/images?q=tbn:ANd9GcQQYeaG_K1m_iAi94IxSj_3tKHiOyhvEw5hDquCJ6ui0tu1DWMsfA

8. Metals http://new.testmagic.com/wp- content/uploads/2012/08/malleable.pn g https://encrypted- tbn3.gstatic.com/images?q=tbn:ANd9Gc RCdH6G0hOn5k4q1Tq3XWuJ_SMrhX9w MIk_4jm7j7LzMaM1NW_T_CJ9iq_O http://users.ox.ac.uk/~sann2616/Image s/Good%20conductor.gif Ductile Good conductors of heat and electricity

9. Metals Are likely to lose electrons, forming positive ions called cations. http://cdn.hsmemes.com/2013/4/16/560630dffea46c5d81a c07a3adadcf27.jpg

10. Alkali Metals Most reactive group of metal elements All contain 1 valence electron Lithium Metal Click on metal to watch a cool you tube video!

11. Alkaline Earth Metals Also a very reactive metal group. Not as reactive as Alkali metals. http://www.periodictable.com/Samples/004.1/s12s.JPG

12. Metalloids Separate the metals from the non-metals Found along the staircase Have properties of both metals and non-metals Are 7 of them http://www.chemtech.org/cn/cn1405/i mage/3-period-table-metals.gif Used in computer chips Used in solar cells

13. Non- Metals Are brittle, poor conductors of heat and electricity and many are gases at room temperature. Are likely to gain electrons to form negatively charged ions or anions. http://images.sciencedaily.com/2013/02/1302261140 23-large.jpg S 2-

14. Halogens Most reactive group of non-metals Found in Group 17 or VII A Fluorine is the queen. Chlorine, Bromine and Iodine at room temperature. Fluorine could not be included due to its high reactivity. http://upload.wikimedia.org/wikipedia/commons/c/c6/Halogens.jpg

15. Noble or Inert Gases Least reactive/ most stable group on the periodic table Each element has 8 valence electrons with the exception of He, which only has 2 https://figures.boundless.com/10100/full/neon-20tubes.png Click on picture to watch a cool video!

16. Transition and Inner Transition Metals http://library.thinkquest.org/3659/pertable/trametal.gif http://library.thinkquest.org/3659/pertable/intmetal.gif d sublevels f sublevels

17. Period vs. Group Period Horizontal rows on table Have principal quantum numbers of 1-7 Elements in a period have different properties because they all have different numbers of valence electrons. All valence electrons occupy the same principal energy level. Group Also known as a family Have similar chemical properties because they all have the same number of valence electrons. Valence electrons occupy different principal energy levels. http://01.edu-cdn.com/files/static/mcgrawhill-images/9780071410113/f0045-01.jpg

18. Numbering the Periodic Table Old Way A groups and B groups – B groups were the transition elements – A groups were the rest Used Roman Numerals to indicate the number of valence electrons for the A groups Valence electrons are important for bonding /chemical properties All elements want 8 valence electrons New Way Numbering the periodic table groups from 1-18 Makes all periodic tables uniform Slightly more difficult to determine valence electrons. (must subtract 10 from groups 13-18)