1. Ch. 10 - Atomic Structure II. Electron Cloud Model (p.272-274)  Orbital  Energy Levels  Bohr Model Diagrams

2. A. Orbital  Region where there is 90% probability of finding an electron.  Can’t pinpoint the location of an electron.  Density of dots represents degree of probability.

3. A. Orbital  Orbitals have different shapes.

4. B. Energy Levels  Electrons can only exist at certain energy levels.  Low energy levels are close to the nucleus.  Each energy level (n) can hold 2n 2 electrons.

5. C. Bohr Model Diagrams  Simplified energy levels using Bohr’s idea of circular orbits. e- Maximum e - Level 12e - Level 28e - Level 318e - Level 432e - Lithium Atomic #:3 Mass: 7 # of p:3 # of e:3 # of n:4 p p n n n n p e- Can replace with: 3p 4n

6. C. Bohr Model Activity  Choose a number between 1 & 18.  Find your element by the atomic number you picked.  Draw a Bohr Model diagram for your element on your marker board. Round off the mass listed on the table and subtract the atomic # to find the # of neutrons. Abbreviate the # of ‘p’ and ‘n’ in the nucleus.  Have a partner check your drawing.  Repeat with a new element.