Question Notes Tool Box: Summary: (Answer EQ- completed after notes) Topic/ Objective: Periodic Table Name Date Essential Question: Explain the organization and trends of the periodic table. Period Tool Box: Summary: (Answer EQ- completed after notes) Question Notes

5.1 Organizing Elements Last Chapter: Mendeleev’s Periodic Table Column is called: Group Row is called: Period Periodic table: elements in columns with properties repeating row-row Mendeleev’s Periodic Table Proposal: arranged the elements into rows in order of increasing mass; similar properties in same column Prediction Not all elements discovered; spaces Close match to new elements

5.2 Modern Periodic Table Periodic Law: pattern of repeating properties Elements are arranged by increasing atomic number (# p+) Row= period; increasing p+ across Column = group; similar properties Atomic Mass amu: atomic mass units, use C-12 atoms are 1/12th mass C-12 Isotopes: different n numbers Weighted avg: ex grading system; avg mass of isotopes Classes of Elements Metals, nonmetals, metalloids (between metals and nonmetals)

5.3 Representative Groups Valence e-: e- occupy the highest E level of atom Alkali metals:1A, increase reactivity top to bottom 104-141-Alkali earth metals 2A: reactivity with water (temp) 142-Boron Family:3A, B metalloid, rest metals; Al most abundant in Earth’s crust 142-Carbon Family:4A, C 2nd abundant in body, 143-Nitrogen Family: 5A, N is common fertilizer 143-Oxygen Family: 6A, O most abundant in Earth’s crust 144-Halogens:7A, different phys appearances but similar chem properties (reactivity, flammability) 145-Noble gases: 8A, colorless/ odorless/ very unreactive