1. Periodic Table Review Be sure the following info is in your notebook or on your yellow Periodic Table COLUMN = “GROUP” Elements with similar chemical and physical properties, and that don’t react with each other ROW = “PERIOD” Elements with similar atomic masses, but chemical and physical properties go through a cycle

2. Predicting Periodically Read instructions as a class up through first paragraph under “PLOTS BY ATOMIC NUMBER 1-36” (ending with “in the rows labeled Estimate”). You’re on your own for the rest. Follow the instructions CAREFULLY so you don’t have to redo your work. You should check your work occasionally with the instructor’s key. Do as much as you can today. Some time will be available tomorrow.

3. Predicting Periodically Estimated values for elements #4 & #23

4. Predicting Periodically Actual values for elements #4 & #23 Eleme nt ValueMP K)BP (K) Density (g/cm 3 ) Radius (Å) #4 Estimate 2950 Actual 155132431.8481.40 #23 Estimate Actual 217536826.111.92

5. Predicting Periodically Sample GROUP Plot

6. WRONG !!

7. Predicting Periodically Same properties in groups (columns) Group 1 H Li Na K Rb Cs Group 18 He Ne Ar Xe Rn

8. Predicting Periodically Repeating pattern of properties in periods (rows) Row 2 Row 3 Row 4

9. Predicting Periodically NEW THEME: Structure of table is determined by structure of atoms TANTALIZING HINT: Atomic radius ALSO has same periods as all the other properties. Atomic radius measures size of electron cloud around atom.