The document summarizes the evolution of atomic models from Dalton's billiard ball model in 1803 to the modern quantum mechanical model. It traces the key discoveries and models of Thomson, Rutherford, Bohr, Schrodinger that led to the understanding that electrons occupy discrete energy levels and orbitals around the nucleus rather than definite orbits, described by quantum numbers. The modern atomic model uses orbitals and quantum mechanics to describe the probability of finding electrons in an atom.

1. Dalton Model 1803 – John Dalton believed that an atom was an indestructible particle with no internal frame. (Billiard Ball Model) Thomson Model 1897 – J.J. Thomson discovers the electron. He believed electrons were embedded in positive charge sphere. (Plum pudding Model) Rutherford Model 1911 – Ernest Rutherford discovers that there is a dense, positively charged nucleus. Electrons go around the nucleus. Bohr Model 1913 – Niels Bohr enhances Rutherford’s model by having electrons move in a circular orbit at fixed distances from the nucleus. The Evolving Atomic Model

13. Study guide for chp. 4 and 5 Atomic structure notes -Know how to calculate atomic mass -Know how to draw bohr model Review worksheets 4.1-4.3 Know what ion an element will form Quantum mechanics notes Know how to write long hand electron configuration Be able to explain the behavior of electrons (i.e., what did you learn from the flame lab?) Review worksheets 5.1-5.2

14. Need to add Relate outer shell to lewis dot and oxidation states