1. Matter Lecture #3 Atoms and the Periodic Table of Elements

2. I. Additional information about atoms A.Atomic Number: Identifies the element and is the same as the number of protons in the nucleus of an atom of an element. B.Atomic Mass: Sum of all protons and neutrons of an atom (round this number to the nearest whole number).

3. I. Additional information about atoms C.You can identify the atomic number and mass from the Periodic Table: Example: 27 Co Cobalt 58.93 Atomic Number Element’s Symbol Element’s Name Atomic Mass

4. 27 Co Cobalt 58.93 From this, you can determine the number of protons, neutrons, electrons, and mass number Protons = Atomic Number Protons = 27 Electrons = Atomic Number Electrons = 27

5. 27 Co Cobalt 58.93 Neutrons = Atomic Mass - Atomic Number Neutrons = 59 – 27 = 32 Mass Number = Protons + Neutrons Mass Number = 27 + 32 = 59

6. You have The Periodic Table of Elements in your Time Tracker and in your Matter Textbook.