2.  Take Notes!

3. Atomic Number Chemical Symbol Chemical Name Atomic Mass 11 Na Sodium 23.0

5. On our Periodic Table, it’s the # on the TOP 11 Na Sodium 23.0 Think APE!!! Atomic number = Protons = Electrons

6. Let’s Practice!!!

7. LET’S PRACTICE…THINK A=P=E 1. A tomic number? 2. Number of Protons? 3. Number of Electrons? 8 O OXYGEN 16 8 8 8

8. 11 Na Sodium 23.0 On our Periodic Tables, it’s the number on the bottom. Notice the # is in decimal form. For our purposes, we will round to the nearest whole #

9. SO… how do we find the # of Neutrons?

10. Mass- Atomic Number = Neutrons

11. What ‘s the A tomic #? How many P rotons are there? How many E lectrons are there? What is the Atomic mass? What part of the Atomic Mass represents the protons? So, if we have 11 protons in the Atomic Mass, how much mass then must represent the Neutrons? 11 Na Sodium 23.0 11 23 11

12. 23 - 11 12 Neutrons

13.  Find the number of protons, neutrons, and electrons in Fluorine!! A=P=E 9 protons, 9 electrons M-A=N 19-9 = 10 Neutrons

14.  Glue in the chart under Application.  Using a pencil & your periodic table, fill in the chart.

15. Chem. Name Chem. Symbol Atomic Number Atomic Mass # of Protons # of Neutrons # of Electrons K 50 36 195 Barium

16.  You found an unknown substance that you had analyzed. The chemist discovered it had 79 protons. What did you find AND how did you know?  In 3-4 sentences, explain what makes every Element on the Periodic Table different.