Chem 1061 1st Edition Lecture 18 Outline of Last Lecture 1 Definitions a Heat of Formation b Heat of Combustion c Heat of Vaporization d Heat of Fusion 2 Determining Heat of Reactions from Heat of Formation 3 Quantum Theory and Atomic Structure a Definitions 4 Electromagnetic Radiation Outline of Current Lecture 5 Calculating Frequency 6 Quantum Theory 7 Rydberg Equation 8 Atomic Model 9 Bohr s Model 10 Bohr s Model of the Hydrogen Atom Current Lecture Calculating Frequency Calculate the Frequency of LiCl emission at 680 nm 3 00 x 10 8 m s 680 nm x V 3 00 x 10 8 m s 6 8 x 10 7 m x V 3 00 x 10 8 m s 6 80 x 10 7 m 4 41 x 10 14 Hz Particle Nature of Light experimental evidence on p 291 293 Quantum Theory Quantum a fixed amount E h x V These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute E Energy of a photon packet of light energy h planks constant 6 626 x 10 34 Js V frequency Calculate the Energy Associated with Violet Light 400 nm Red Light 700nm E hc Violet E 6 626 x 10 34 Js 3 00 x 10 8 m s 4 00 x 10 7m 4 97 x 10 19 J Red E 6 626 x 10 34 Js 3 00 x 10 8 m s 7 00 x 10 7 m 2 84 x 10 19 J Violet has higher energy but a smaller wavelength they are inversely proportional The atomic spectra is more evidence for the particle nature of light Rydberg Equation Allow us to predict position wavelength of line in H atom 1 R 1 n1 2 1 n2 2 wavelength of observed light R Rydberg constant not a gas constant 1 096776 x 10 7 m 1 n different shells in the atom integers n2 n1 Use Rydberg Equation to find in nm of the photo emitted when a H atom undergoes a transition from n 5 to n 2 1 1 096776 x 10 7 m 1 1 4 1 25 1 2303229 6 m 1 1 2303229 6m 434 nm Atomic Model e spirals towards p the atom would collapse Bohr s Model e only allowed in certain models quantized fixed number Bohr s Model of the Hydrogen Atom 1 Stationary States fixed levels 2 E don t emit energy in stationary state 3 E can change stationary state by absorbing or emitting energy light E photon E atom E final E initial h x V N quantum number describes what stationary state you re in Ground state lowest energy level stationary state for H e in n 1 Excited state e in orbit further from nucleus for H e in n 1 Bohr s model works for any 1 e species H z 1 He z 2 Li2 z 3 etc
View Full Document
Unlocking...