CHAPTER #4 ATOMIC STRUCTURE

Objectives/Outcomes: Things you will be able to do Define Atom. List and Describe the Models of the Atom. Name and Describe the Parts of an Atom Identify the Relationships Among the Atomic #, Isotopes, Mass #, & Average Atomic Mass of an Atom. Calculate the Numbers of Protons, Neutrons, & Electrons of an Atom Given Its Symbol and Mass Number. Calculate the Average Atomic Mass of an Atom

Structure of an Atom ATOMS: Democritus (Greek Philosopher, 4th Century BC) ‘atomos” = Indivisible 100 different naturally occurring atoms that are called…………

Models of an Atom: A look into the past 200 years of Research DALTON’S MODEL: EARLY 1800’S, 4 MAIN CONCEPTS 1. 2. 3. 4.

Models of an Atom: A look into the past 200 years of Research THOMSON’S MODEL: late 1800’s ATOMS are electrically neutral so what had to be present to make the ATOM electrically neutral?

Models of an Atom: A look into the past 200 years of Research RUTHERFORD’S MODEL: 1911, FOUND (+) CHARGE

Models of an Atom: A look into the past 200 years of Research BOHR’S MODEL: 1913

Models of an Atom: A look into the past 200 years of Research ELECTRON CLOUD MODEL: NOW

ATOMIC ORBITALS AND ELECTRON CONFIGURATION Stable Atom: Unstable Atom: http://tw.video.yahoo.com/video/play?vid=193831 ATOMIC ORBITALS: Energy Level Max # of e- 1 2 3 4

PROTONS: (P+) Positive Charge INSIDE THE NUCLEUS PROTONS: (P+) Positive Charge In 1932 James Chadwick, a former student of Rutherford, stated that the Nucleus is more complicated than previously thought. He discovered……… Q: How are p+ and n packed together so tightly? A:

ATOMIC NUMBER: Atomic # Examples: Sodium (Na) Iron (Fe) Q: How many electrons does each Element have? A: #

HOW MANY NEUTRONS DOES EACH ELEMENT HAVE? The # of Neutrons can be….

MASS NUMBER / ATOMIC MASS Q: What is the difference between C-12 and C-14? Q: What units do we place by these Mass #’s?

Average Atomic Mass: Sum of the masses of all the Elements Isotopes