1. PERIODIC TABLE

2. Dmitri Mendeleev  Russian chemist / school teacher  Youngest of 17 children  Noticed trends in the known elements  PERIODIC LAW:  When elements are arranged in order of increasing relative mass, certain sets of properties recur periodically

3. Dmitri Mendeleev  His initial organization of the elements is the basis of our modern periodic table  We will explain the reason for these trends later on

4. PERIODIC TABLE  Use your periodic table to take notes  Periodic table is divided into columns and rows  Columns are called GROUPS. Groups have elements with similar properties.  Rows are called PERIODS. Periods have elements with similar electron configuration.

5. METALS VS. NONMETALS  Look at the periodic table at the front of the class.  Find the red “stair shaped” line located at the right of the list. It starts with B (boron)  This divides the metals (to the left of the line); and  The nonmetals (to the right of the line)  Note this line on your periodic table

6. METALS VS. NONMETALS  Metals:  Good conductors of heat and electricity  Malleable: can be pounded flat  Ductibility: can be drawn into wires  Often shiny  Tend to lose electrons in chemical reactions  Transition metals: the metals locate in group 3-12

7. NONMETALS  Nonmetals:  Poor conductors of heat and electricity  Much more varied properties than metals  Some are solids and some are gases at room temperature  Tend to gain electrons in chemical reactions

8. METALLOIDS (SEMICONDUCTORS)  Elements located near the line dividing metals and nonmetals are sometimes called semiconductors or metalloids:  Boron (B)  Silicon (Si) – very important for computers  Germanium (Ge)  Arsenic (As)  Antimony (Sb)  Tellurium (Te)  Astatine (At)

9. METALLOIDS  Metalloids have intermediate conductivity for electricity  This conductivity can be changed and controlled  Very useful for the binary language of computers

10. MAIN GROUP ELEMENTS  Main group elements: These elements have predictable behaviors based on their position on the periodic table.  Predictability is based on the GROUPS, or the columns in the Periodic table

11. GROUP 1 (OR IA)  Group 1 is located in column 1.  This group is called the Alkali metals  Alkali metals are very active metals  For example: Pure sodium added to water creates a huge explosion.  Alkali metals are soft and can be cut with a knife  When they undergo chemical reactions, they tend to lose 1 electron and produce a (+1) charge

12. GROUP 2 (OR IIA)  Group 2 is located in column 2.  This group is called the Alkali earth metals  Alkali earth metals are fairly reactive, but not as reactive as Alkali metals  For example: Magnesium gives off a very bright, white light when lit.  Harder, denser and stronger metals  When they undergo chemical reactions, they tend to lose 2 electron and produce a (+2) charge

13. GROUP 7 (OR VIIA)  Group 7 is located in column 17.  This group is called the Halogens  Very reactive nonmetals  Often gaseous at room temperature  Elements are often used to sterilize (chlorine or bromine in pools; fluorine in the water)  When they undergo chemical reactions, they tend to gain 1 electron and produce a (-1) charge

14. GROUP 8 (OR VIIIA)  Group 8 is located in column 18.  This group is called the Noble Gases  Chemically inert (does not undergo chemical reactions)  For example: Balloons now use Helium gas instead of Hydrogen  Noble gases do not gain or lose electrons without lots of energy

15. LATHANIDES  Have atomic numbers from 58-71  Elements that come after the element, Lanthanum (La)  Shiny, reactive metals  Irregular electron configurations

16. ACTINIDES  Have atomic numbers from 90-103  Elements that come after the element Actinium (Ac)  All actinides are radioactive  Example: Nuclear fission of uranium produces a large amount of energy as produced in a nuclear missile or atomic reactor.

17. TRANSITION METALS  Not as predictable in how they behave  They may lose different number of electrons in reactions  Example:  Iron can lose 2 or 3 e- in a reaction and make  Fe +2  Fe +3

18. MAKE SURE YOU HAVE LABELED YOUR PERIODIC TABLES  Have the following groups  Metals/Nonmetals/Metalloids  Alkali metals  Alkali earth metals  Halogens  Noble gases  Also the following periods  Lanthanides  Actinides  Transition metals