How elements are organized Chapter 2 Section 1

Introduction Scientists started to organize elements in the 1700s Tried to group according to their properties

Mendeleev’s Periodic Table Mendeleev, a teacher and chemists, was writing a text book and needed a way to organize the elements Created a set of cards Each card had Element Mass Known properties Figured to organize them by their Atomic Mass

Periods and Groups Periods go from left to right Groups go up and down

Periodic Table Called the Periodic Table because of the repeating pattern Columns are called groups or families Similar but not identical Rows are called periods Interval between repetitions

Predicting the Future What do you notice about Mendeleev's table below

Modern Periodic Table Still organized using the Mendeleev’s concept just more detailed information

Complete Atomic Structure and Periodic Table Worksheet on the back

Bill Nye-atoms and molecules Complete worksheet on the back of page 5 (guided reading 1.1)