L06S08 Matter Waves - Chem 1A L6:"Matter Waves"...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Chem 1A L6:"Matter Waves" Lab 3: Goal: Determine how effective a sunscreen is at absorbing radiation by measuring the extinction coefficient of the active ingredients. Tools and Skills: : UV-Vis absorption UVspectroscopy, Beer's Law, and dilution calculations. This is the FIRST formal report. Guidelines are on pages 11-12 of the Lab Manual. 11 2002 A.Pines,M.Kubinec, UCB L6-1 Electromagnetic Spectrum 400 Summary 500 600 Visible x-rays UV IR MW The Particle Nature of Light Light Intensity 700 nm -rays Radio, NMR, MRI 10-16 10-12 10-8 A.Pines,M.Kubinec,UCB 10-4 100 104 108 m L7-4 2002 A.Pines,M.Kubinec, UC Ephoton = h L8-6 Photoelectric Effect The Particle Nature of Light Light-Wave / Particle LightDuality Wave (length) I II e Ekin Particle (Momentum) c Wave h = p Duality p=mc Particle p= h Ephoton = h A.Pines,M.Kubinec,UCB Ekin= h - = h - ho h L7-2 2002 A.Pines,M.Kubinec, UCB A.Pines,M.Kubinec,UCB L6-2 L7-6 Diffraction and Interference Intensity A+B Probability Distribution ~ ~ L6-3 2002 A.Pines,M.Kubinec, UCB A.Pines,M.Kubinec,UCB 1 Chem 1A L6:"Matter Waves" Matter Particles and Waves Momentum : 2 e- p=mv p=mv Particle p= h h=6.62 x 10-34 Js ~ Probability v Wave Duality h = p L6-4 2002 A.Pines,M.Kubinec, UCB Summary Particles and Waves Momentum Matter Particle Photon (yellow) (yellow) e- (v ~ 105 m sec-1) Na (80K, v~300 m sec-1) Baseball (170g, v~40 m sec-1) L6-4 A.Pines,M.Kubinec,UCB DeBroglie (nm) ~ 600 ~6 ~ 0.06 ~ 6x10-26 L8-3 : 2 ~ Probability v 2 e- p=mv p=mv Particle h p= h=6.62 x 10-34 Js Wave Duality h = p 2002 A.Pines,M.Kubinec, UC Discrete, Quantized States Standing Waves (x) E n 3 2 1 Nodes 2 1 0 L6-11 Absorption and Emission Spectra E=h E=h Excited States + + + - Ground State + 2002 A.Pines,M.Kubinec, UCB 2002 A.Pines,M.Kubinec, UC A.Pines,M.Kubinec,UCB L6-5 L8-7 Diffraction and Interference Intensity A+B Probability Distribution ~ ~ L6-6 2002 A.Pines,M.Kubinec, UCB A.Pines,M.Kubinec,UCB 2 Chem 1A L6:"Matter Waves" De Broglie Wavelengths Particle Photon (yellow) (yellow) e- (v ~ 105 m sec-1) Na (80K, v~300 m sec-1) Baseball (170g, v~40 m sec-1) 2002 A.Pines,M.Kubinec, UCB de Broglie (nm) ~ 600 ~6 ~ 0.06 ~ 6x10-26 L6-7 Electron Microscopy 2002 A.Pines,M.Kubinec, UCB L6-8 ChemQuiz 6.1 About how many photons are needed to ~stop the Na atom? A) ~1 ~1 2002 A.Pines,M.Kubinec, UCB 23Na h ~ 600 nm 80 K B) ~102 ~10 C) ~104 ~10 L6-9 A.Pines,M.Kubinec,UCB 3 Chem 1A L6:"Matter Waves" ChemQuiz 6.2 Electrons with ~ 4 nm are heated to x 4 their kinetic energy. What is energy. the new (nm)? eEkin=mv2 Ekin=p2/2m A) ~ 1 2002 A.Pines,M.Kubinec, UCB B) ~ 2 C) ~ 8 L6-11 Discrete, Quantized States Standing Waves (x) E n 3 2 1 Nodes 2 1 0 L6-13 Excited States + + + - Ground State 2002 A.Pines,M.Kubinec, UCB + An electron as a standing wave around the nucleus 2002 A.Pines,M.Kubinec, UCB L6-14 A.Pines,M.Kubinec,UCB 4 Chem 1A L6:"Matter Waves" Absorption and Emission Spectra Electronic Transtions v E = h 2002 A.Pines,M.Kubinec, UCB L6-15 ChemQuiz 6.3 Shown is an energy energy level scheme and the emission spectrum. Which line arises from 3 1? 3 2 1 A B C E C) C L6-16 A) A 2002 A.Pines,M.Kubinec, UCB B) B ChemQuiz 6.4 To which energy-level energyscheme does the emission spectrum correspond? A) 2002 A.Pines,M.Kubinec, UCB B) C) L6-18 A.Pines,M.Kubinec,UCB 5 Chem 1A L6:"Matter Waves" Lecture Complete 2002 A.Pines,M.Kubinec, UCB L6-20 A.Pines,M.Kubinec,UCB 6 ...
View Full Document

This note was uploaded on 04/03/2008 for the course CHEM 1A taught by Professor Nitsche during the Spring '08 term at University of California, Berkeley.

Ask a homework question - tutors are online