Periodic Table Notes 
         History               Dimitri Mendeleev (1860s)                                                                  Each energy level can hold a specific # of electrons 
                               Noticed patterns when elements were arranged in                                            Level 1 (closest to nucleus) = 2 e- max 
                                                                                                                                         -
                                order of increasing ___________________________________                                    Level 2 = 8 e max 
                                                                                                                                         -
                               Noticed blank spaces left on his table and concluded                                       Level 3 = 8 e max 
                                they were spaces for ________________________________                 Valence              Electrons located in the ______________________________ 
         Modern                (early 1900s to present)                                              Electrons            VERY important because they determine an element’s 
         Periodic Table        Arranged in order of increasing                                                             ___________________________ 
                                ________________________________________ (# of protons)                                    They have the ___________________________________ and 
         Groups/               Up & down                                                                                   are involved when elements form _____________________ 
         Families              Columns                                                               Valence              Group #          # VEs                 Reactivity 
                               Elements in a group/family have ______________________                Electrons and           1                          
                               because they have the same number of                                  Periodic Table          2                          
                                                                                                      Patterns 
                                _______________________________                                                               13                        ------------------------------------------- 
         Periods               Side to side                                                                                  14                        ------------------------------------------- 
                               Rows                                                                                          15                        ------------------------------------------- 
                               Atoms in the same period have the same number of                                              16                        ------------------------------------------- 
                                _______________________________                                                                                          
         Symbols/              Symbols always have ONE capital letter                                                        17         
         Names                 Original names of some elements from Latin,  Greek or                                         18                         
                                other origin – remains in symbol                                      Electron Dot         Show 
         PEROPERTIES           Valence electrons (VE) = _____                                        Diagrams              the # of 
         Hydrogen              Reactivity = __________________                                                             VEs of 
         Stands Apart          Colorless, odorless gas at room temp; low density                                           an 
         Group 1:              Valence Electrons (VE) = _____                                                              element 
         ALKALI METALS         Reactivity = __________________                                       Octet Rule           The rule of 8 
                               Soft, silver colored, shiny, low density                                                   Atoms are stable when they have a 
         Groups: 2 – 16        Reactivity = decreases then slowly increases from left to                                   _______________________ __________________________ 
                                right                                                                                       (they “want” a complete octet) 
         Group 17:             Valence Electrons (VE) = _____                                                             They will _______________________________________ in 
         Halogens              Reactivity = __________________                                                             order to reach 8 valence electrons 
                               Poor conductors, react violently with alkali metals to                                     A full outermost energy level of electrons = 
                                form salts, never found uncombined in nature                                                ________________ 
         Group 18:             Valence Electrons (VE) = _____                                                             Noble gases already have a full octet! STABLE! NOBLE! 
         Noble Gases           EXCEPTION: _____has _____VEs                                                               Atoms on the LEFT of the Periodic Table tend to 
                               Reactivity = __________________                                                             ____________ their VEs to get to a full outer energy level 
                               Colorless, odorless gases at room temp                                                     Atoms on the RIGHT side tend to ____________ VEs to get 
         Atomic                                                                                                             a full octet 
         Structures                                                                                  
         Bohr Model