First Periodic Table Mendelevs Periodic Table - presented a way to organize the known elements - organized elements by properties - arranged rows by increasing atomic mass - arranged columns by shared similar chemical (change in chemical make up) and physical (change in appearance) properties

Changes to the Periodic Table There are places where the atomic mass DOES NOT increase from left to right, Nickel and Cobalt Instead of atomic mass increasing it now is increasing atomic number

Modern Periodic Table - Consists of boxes containing info such as: element name, symbol, atomic number, atomic mass Horizontal rows called PERIODS #1-7 - Vertical columns called GROUPS #1-18 elements in the same group have the same properties

Regions on the Periodic Table The elements increase by one proton and one neutron as you move from left to right across a period. As you move left to right metals are less reactive METALS Occur as solids at room temp Shiny, can be pounded into wires or sheets of metal Good conductors NON- METALS Most are gases at room temp Poor conductors METALLOIDS - Exhibit properties of both metals and non metals

-Go to the website below Quizlet Review -Go to the website below https://quizlet.com/240703885/periodic-table-the-periodic- table-flash-cards/ -Do each of the tabs on the Quizlet for the Periodic Table and take notes if needed At the end of your notes in your INB p.23 make 4 sentence summary of what you learned using the website