4/14/2015. Models of the Atom. Quantum Physics versus Classical Physics The Thirty-Year War ( ) Classical Model of Atom

Size: px
Start display at page:

Download "4/14/2015. Models of the Atom. Quantum Physics versus Classical Physics The Thirty-Year War ( ) Classical Model of Atom"

Transcription

1 Quantum Physics versus Classical Physics The Thirty-Year War ( ) Models of the Atom Interactions between Matter and Radiation Models of the Atom Bohr s Model of the Atom Planck s Blackbody Radiation 1897 Thomson s Plum Pudding Model and the Discovery of the Electron 1911 Rutherford s Model and the Discovery of the Nucleus 1913 Bohr s Planetary Model and Spectral Lines 1926 Schrödinger s Cloud Model and the Probability Wave Function Einstein s Photoelectric Effect Compton s Effect De Broglie s Matter Waves Quantum Mechanics Bohr s Model of the Atom Classical Model of Atom Classical Model of the Atom Atomic Spectra 1913 Bohr s Planetary Model Atomic Spectra Explained Energy-Level Diagrams Atomic Spectra 1

2 1913 Bohr s Planetary Model Atomic Spectra Explained Energy-Level Diagrams 1900 Planck s Blackbody Radiation Thermal Radiation Blackbody Blackbody Radiation The UV Catastrophe Blackbody Explained by Bohr s Atom 2

3 Thermal Radiation Blackbody Blackbody Radiation Power (area under curve) increases with T Stefan-Boltzmann s Law P = A e T 4 Peak wavelength decreases as T increases Wien s Law max T = m K Stars Surface Temperatures 3

4 Sun s Spectrum Formative Quiz The temperature of your skin is approximately 35 0 C. (a) What is the peak wavelength of the radiation it emits? (b) What is the total power emitted by your skin. Assume that the area of your skin is 2.0 m 2. (c) Why don t you glow as bright as a light bulb? The UV Catastrophe Blackbody Explained by Bohr s Atom Our Universe is a Blackbody (Cosmology and Quantum Physics) 1905 Einstein s Photoelectric Effect Albert Einstein Nobel Prize 1921 Experiment Classical Physics Experimental Results Einstein s Interpretation Applications 4

5 Experiment Classical Physics vs Experimental Results Einstein s Interpretation K max = h f - Applications Automatic Door Openers K max maximum kinetic energy of elected electrons (photoelectrons) h Planck s constant f frequency of light work function of the metal Medicine Film 5

6 Photomultiplier Tube Automatic Camera Smoke Detector Solar Panels Formative Quiz The maximum electron energy in a photoelectric experiment is 3.4 ev. When the wavelength of the illuminating radiation is increased by 25%, the maximum electron energy drops to 2.6 ev. (a) What is the original wavelength of the illuminating radiation? (b) What is the work function of the emitting surface? 6

7 1923 Compton s Effect Experiment Arthur Compton Nobel Prize 1927 Experiment Classical Physics Experimental Results Compton s Interpretation Applications Classical Physics vs Experimental Results Compton s Interpretation Photons have momentum p = h / Compton Shift = - 0 = (h / (me c)) (1 cos ) Compton s Wavelength of Electron C = h / (me c) = nm Application Formative Quiz Dental X - Rays X-rays of wavelength = 22 pm are scattered from a carbon target and the scattered x-rays are detected at 85 0 to the incident beam. (a) What is the Compton shift of the scattered x-rays? (b) What percentage of the initial x-ray energy is transferred to an electron in such scattering? 7

8 Photons and Electromagnetic Waves 1923 De Broglie s Matter Waves Louis De Broglie Nobel Prize 1929 Shortest doctoral thesis on record Matter Waves Electron Diffraction and Interference Patterns Application: The Electron Microscope Matter Waves Electron Diffraction Pattern De Broglie s wavelength = h / p = h / (m v) frequency of a particle f = E/h Equations contain both particle (p and E) and wave ( and f) quantities. The Electron Microscope Head of an Antarctic Mite magnified 1500 times 3-D nanostructure: flowers" of silicon carbide and gallium Hydrothermal Worm 8

9 Quantum Mechanics 1925 Heisenberg s Uncertainty Principle 1925 Heisenberg s Uncertainty Principle Barrier Tunnelling Applications 1926 Schrödinger s Cloud Model Probability Density and Electron s Orbitals x p x h / 4 E t h / 4 Schrödinger's Cat Barrier Tunnelling Applications Alpha Decay Nuclear Fusion Scanning Tunnelling Microscope Alpha Decay and Quantum Tunnelling Kinetic Energy of Alpha Particles and Half-Life Radionuclide Q K Half-Life 238U 4.25 MeV 4.5 x 10 9 yr 228U 6.81 MeV 9.1 min The alpha particle tunnels through the barrier, escaping the nucleus. Higher-energy alpha particles come from nuclei with shorter half-lives. 9

10 Scanning Tunnelling Microscope 1926 Schrödinger s Cloud Model Probability Density and Electron s Orbitals Schrödinger s Cat 10

12/04/2012. Models of the Atom. Quantum Physics versus Classical Physics The Thirty-Year War ( )

12/04/2012. Models of the Atom. Quantum Physics versus Classical Physics The Thirty-Year War ( ) Quantum Physics versus Classical Physics The Thirty-Year War (1900-1930) Interactions between Matter and Radiation Models of the Atom Bohr s Model of the Atom Planck s Blackbody Radiation Models of the

More information

CHAPTER 27 Quantum Physics

CHAPTER 27 Quantum Physics CHAPTER 27 Quantum Physics Units Discovery and Properties of the Electron Planck s Quantum Hypothesis; Blackbody Radiation Photon Theory of Light and the Photoelectric Effect Energy, Mass, and Momentum

More information

Planck s Quantum Hypothesis Blackbody Radiation

Planck s Quantum Hypothesis Blackbody Radiation Planck s Quantum Hypothesis Blackbody Radiation The spectrum of blackbody radiation has been measured(next slide); it is found that the frequency of peak intensity increases linearly with temperature.

More information

Chapter 27. Quantum Physics

Chapter 27. Quantum Physics Chapter 27 Quantum Physics Need for Quantum Physics Problems remained from classical mechanics that relativity didn t explain Blackbody Radiation The electromagnetic radiation emitted by a heated object

More information

Chapter 37 Early Quantum Theory and Models of the Atom. Copyright 2009 Pearson Education, Inc.

Chapter 37 Early Quantum Theory and Models of the Atom. Copyright 2009 Pearson Education, Inc. Chapter 37 Early Quantum Theory and Models of the Atom Planck s Quantum Hypothesis; Blackbody Radiation Photon Theory of Light and the Photoelectric Effect Energy, Mass, and Momentum of a Photon Compton

More information

Early Quantum Theory & Models of the Atom (Ch 27) Discovery of electron. Blackbody Radiation. Blackbody Radiation. J. J. Thomson ( )

Early Quantum Theory & Models of the Atom (Ch 27) Discovery of electron. Blackbody Radiation. Blackbody Radiation. J. J. Thomson ( ) Early Quantum Theory & Models of the Atom (Ch 27) Discovery of electron Modern physics special relativity quantum theory J. J. Thomson (1856-1940) measured e/m directly set-up was similar to mass spectrometer

More information

General Physics (PHY 2140)

General Physics (PHY 2140) General Physics (PHY 2140) Lecture 27 Modern Physics Quantum Physics Blackbody radiation Plank s hypothesis http://www.physics.wayne.edu/~apetrov/phy2140/ Chapter 27 1 Quantum Physics 2 Introduction: Need

More information

Preview. Atomic Physics Section 1. Section 1 Quantization of Energy. Section 2 Models of the Atom. Section 3 Quantum Mechanics

Preview. Atomic Physics Section 1. Section 1 Quantization of Energy. Section 2 Models of the Atom. Section 3 Quantum Mechanics Atomic Physics Section 1 Preview Section 1 Quantization of Energy Section 2 Models of the Atom Section 3 Quantum Mechanics Atomic Physics Section 1 TEKS The student is expected to: 8A describe the photoelectric

More information

Constants & Atomic Data. The birth of atomic physics and quantum mechanics. debroglie s Wave Equations. Energy Calculations. λ = f = h E.

Constants & Atomic Data. The birth of atomic physics and quantum mechanics. debroglie s Wave Equations. Energy Calculations. λ = f = h E. Constants & Atomic Data The birth of atomic physics and quantum mechanics Honors Physics Don Rhine Look inside back cover of book! Speed of Light (): c = 3.00 x 10 8 m/s Elementary Charge: e - = p + =

More information

The birth of atomic physics and quantum mechanics. Honors Physics Don Rhine

The birth of atomic physics and quantum mechanics. Honors Physics Don Rhine The birth of atomic physics and quantum mechanics Honors Physics Don Rhine Constants & Atomic Data Look inside back cover of book! Speed of Light (vacuum): c = 3.00 x 10 8 m/s Elementary Charge: e - =

More information

Chapter 27. Quantum Physics

Chapter 27. Quantum Physics Chapter 27 Quantum Physics Need for Quantum Physics Problems remained from classical mechanics that relativity didn t explain Blackbody Radiation The electromagnetic radiation emitted by a heated object

More information

PHYSICS 3204 PUBLIC EXAM QUESTIONS (Quantum pt.1)

PHYSICS 3204 PUBLIC EXAM QUESTIONS (Quantum pt.1) PHYSICS 3204 PUBLIC EXAM QUESTIONS (Quantum pt.1) NAME: August 2009--------------------------------------------------------------------------------------------------------------------------------- 11 41.

More information

General Physics (PHY 2140) Lecture 14

General Physics (PHY 2140) Lecture 14 General Physics (PHY 2140) Lecture 14 Modern Physics 1. Relativity Einstein s General Relativity 2. Quantum Physics Blackbody Radiation Photoelectric Effect X-Rays Diffraction by Crystals The Compton Effect

More information

Physics 1C. Lecture 28D

Physics 1C. Lecture 28D Physics 1C Lecture 28D "I ask you to look both ways. For the road to a knowledge of the stars leads through the atom; and important knowledge of the atom has been reached through the stars." --Sir Arthur

More information

Chapter 7: The Quantum-Mechanical Model of the Atom

Chapter 7: The Quantum-Mechanical Model of the Atom C h e m i s t r y 1 A : C h a p t e r 7 P a g e 1 Chapter 7: The Quantum-Mechanical Model of the Atom Homework: Read Chapter 7. Work out sample/practice exercises Check for the MasteringChemistry.com assignment

More information

Chapter 37 Early Quantum Theory and Models of the Atom

Chapter 37 Early Quantum Theory and Models of the Atom Chapter 37 Early Quantum Theory and Models of the Atom Units of Chapter 37 37-7 Wave Nature of Matter 37-8 Electron Microscopes 37-9 Early Models of the Atom 37-10 Atomic Spectra: Key to the Structure

More information

Physics 1302, Exam 4 Review

Physics 1302, Exam 4 Review c V Andersen, 2006 1 Physics 1302, Exam 4 Review The following is a list of things you should definitely know for the exam, however, the list is not exhaustive. You are responsible for all the material

More information

Particles and Waves Particles Waves

Particles and Waves Particles Waves Particles and Waves Particles Discrete and occupy space Exist in only one location at a time Position and velocity can be determined with infinite accuracy Interact by collisions, scattering. Waves Extended,

More information

Lecture 6 - Atomic Structure. Chem 103, Section F0F Unit II - Quantum Theory and Atomic Structure Lecture 6. Lecture 6 - Introduction

Lecture 6 - Atomic Structure. Chem 103, Section F0F Unit II - Quantum Theory and Atomic Structure Lecture 6. Lecture 6 - Introduction Chem 103, Section F0F Unit II - Quantum Theory and Atomic Structure Lecture 6 Light and other forms of electromagnetic radiation Light interacting with matter The properties of light and matter Lecture

More information

Historical Background of Quantum Mechanics

Historical Background of Quantum Mechanics Historical Background of Quantum Mechanics The Nature of Light The Structure of Matter Dr. Sabry El-Taher 1 The Nature of Light Dr. Sabry El-Taher 2 In 1801 Thomas Young: gave experimental evidence for

More information

AP Physics Study Guide Modern Physics I. Atomic Physics and Quantum Effects 1. Who is generally credited with the discovery of the electron?

AP Physics Study Guide Modern Physics I. Atomic Physics and Quantum Effects 1. Who is generally credited with the discovery of the electron? AP Physics Study Guide Modern Physics I. Atomic Physics and Quantum Effects 1. Who is generally credited with the discovery of the electron? 2. What was it that J. J. Thomson actually measured? 3. Regarding

More information

THE NATURE OF THE ATOM. alpha particle source

THE NATURE OF THE ATOM. alpha particle source chapter THE NATURE OF THE ATOM www.tutor-homework.com (for tutoring, homework help, or help with online classes) Section 30.1 Rutherford Scattering and the Nuclear Atom 1. Which model of atomic structure

More information

Class 21. Early Quantum Mechanics and the Wave Nature of Matter. Physics 106. Winter Press CTRL-L to view as a slide show. Class 21.

Class 21. Early Quantum Mechanics and the Wave Nature of Matter. Physics 106. Winter Press CTRL-L to view as a slide show. Class 21. Early and the Wave Nature of Matter Winter 2018 Press CTRL-L to view as a slide show. Last Time Last time we discussed: Optical systems Midterm 2 Today we will discuss: Quick of X-ray diffraction Compton

More information

Lecture Outline Chapter 30. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc.

Lecture Outline Chapter 30. Physics, 4 th Edition James S. Walker. Copyright 2010 Pearson Education, Inc. Lecture Outline Chapter 30 Physics, 4 th Edition James S. Walker Chapter 30 Quantum Physics Units of Chapter 30 Blackbody Radiation and Planck s Hypothesis of Quantized Energy Photons and the Photoelectric

More information

Chapter 39. Particles Behaving as Waves

Chapter 39. Particles Behaving as Waves Chapter 39 Particles Behaving as Waves 39.1 Electron Waves Light has a dual nature. Light exhibits both wave and particle characteristics. Louis de Broglie postulated in 1924 that if nature is symmetric,

More information

5.111 Principles of Chemical Science

5.111 Principles of Chemical Science MIT OpenCourseWare http://ocw.mit.edu 5.111 Principles of Chemical Science Fall 2008 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms. 5.111 Lecture Summary

More information

Outline Chapter 9 The Atom Photons Photons The Photoelectron Effect Photons Photons

Outline Chapter 9 The Atom Photons Photons The Photoelectron Effect Photons Photons Outline Chapter 9 The Atom 9-1. Photoelectric Effect 9-3. What Is Light? 9-4. X-rays 9-5. De Broglie Waves 9-6. Waves of What? 9-7. Uncertainty Principle 9-8. Atomic Spectra 9-9. The Bohr Model 9-10. Electron

More information

Particle nature of light & Quantization

Particle nature of light & Quantization Particle nature of light & Quantization A quantity is quantized if its possible values are limited to a discrete set. An example from classical physics is the allowed frequencies of standing waves on a

More information

Problems with Classical Physics. Blackbody Radiation Photoelectric Effect Compton Effect Bohr Model of Atom

Problems with Classical Physics. Blackbody Radiation Photoelectric Effect Compton Effect Bohr Model of Atom The Quantum Gang Problems with Classical Physics Blackbody Radiation Photoelectric Effect Compton Effect Bohr Model of Atom Why this shape? Why the drop? Blackbody Radiation A black body is an ideal system

More information

Quantum and Atomic Physics - Multiple Choice

Quantum and Atomic Physics - Multiple Choice PSI AP Physics 2 Name 1. The Cathode Ray Tube experiment is associated with: (A) J. J. Thomson (B) J. S. Townsend (C) M. Plank (D) A. H. Compton 2. The electron charge was measured the first time in: (A)

More information

Stellar Astrophysics: The Interaction of Light and Matter

Stellar Astrophysics: The Interaction of Light and Matter Stellar Astrophysics: The Interaction of Light and Matter The Photoelectric Effect Methods of electron emission Thermionic emission: Application of heat allows electrons to gain enough energy to escape

More information

Einstein. Quantum Physics at a glance. Planck s Hypothesis (blackbody radiation) (ultraviolet catastrophe) Quantized Energy

Einstein. Quantum Physics at a glance. Planck s Hypothesis (blackbody radiation) (ultraviolet catastrophe) Quantized Energy Quantum Physics at a glance Quantum Physics deals with the study of light and particles at atomic and smaller levels. Planck s Hypothesis (blackbody radiation) (ultraviolet catastrophe) Quantized Energy

More information

Announcements. Lecture 8 Chapter. 3 Wave & Particles I. EM- Waves behaving like Particles. The Compton effect (Arthur Compton 1927) Hypothesis:

Announcements. Lecture 8 Chapter. 3 Wave & Particles I. EM- Waves behaving like Particles. The Compton effect (Arthur Compton 1927) Hypothesis: Announcements HW3: Ch.3-13, 17, 23, 25, 28, 31, 37, 38, 41, 44 HW3 due: 2/16 ** Lab manual is posted on the course web *** Course Web Page *** http://highenergy.phys.ttu.edu/~slee/2402/ Lecture Notes,

More information

is the minimum stopping potential for which the current between the plates reduces to zero.

is the minimum stopping potential for which the current between the plates reduces to zero. Module 1 :Quantum Mechanics Chapter 2 : Introduction to Quantum ideas Introduction to Quantum ideas We will now consider some experiments and their implications, which introduce us to quantum ideas. The

More information

Quantum Physics and Atomic Models Chapter Questions. 1. How was it determined that cathode rays possessed a negative charge?

Quantum Physics and Atomic Models Chapter Questions. 1. How was it determined that cathode rays possessed a negative charge? Quantum Physics and Atomic Models Chapter Questions 1. How was it determined that cathode rays possessed a negative charge? 2. J. J. Thomson found that cathode rays were really particles, which were subsequently

More information

1 Photoelectric effect - Classical treatment. 2 Photoelectric effect - Quantum treatment

1 Photoelectric effect - Classical treatment. 2 Photoelectric effect - Quantum treatment 1 OF 5 NOTE: This problem set is to be handed in to my mail slot (SMITH) located in the Clarendon Laboratory by 5:00 PM Tuesday, 10 May. 1 Photoelectric effect - Classical treatment A laser beam with an

More information

Exam 2 Development of Quantum Mechanics

Exam 2 Development of Quantum Mechanics PHYS40 (Spring 00) Riq Parra Exam # (Friday, April 1 th, 00) Exam Development of Quantum Mechanics Do NOT write your name on this exam. Write your class ID number on the top right hand corner of each problem

More information

PSI AP Physics How was it determined that cathode rays possessed a negative charge?

PSI AP Physics How was it determined that cathode rays possessed a negative charge? PSI AP Physics 2 Name Chapter Questions 1. How was it determined that cathode rays possessed a negative charge? 2. J. J. Thomson found that cathode rays were really particles, which were subsequently named

More information

Exam 4. P202 Spring 2004 Instructor: Prof. Sinova

Exam 4. P202 Spring 2004 Instructor: Prof. Sinova Exam 4 P202 Spring 2004 Instructor: Prof. Sinova Name: Date: 4/22/04 Section: All work must be shown to get credit for the answer marked. You must show or state your reasoning. If the answer marked does

More information

1 The Cathode Rays experiment is associated. with: Millikan A B. Thomson. Townsend. Plank Compton

1 The Cathode Rays experiment is associated. with: Millikan A B. Thomson. Townsend. Plank Compton 1 The Cathode Rays experiment is associated with: A B C D E Millikan Thomson Townsend Plank Compton 1 2 The electron charge was measured the first time in: A B C D E Cathode ray experiment Photoelectric

More information

Quantum Theory of Light

Quantum Theory of Light King Saud University College of Applied Studies and Community Service Department of Natural Sciences Quantum Theory of Light General Physics II PHYS 111 Nouf Alkathran nalkathran@ksu.edu.sa Outline Definition

More information

Explain how Planck resolved the ultraviolet catastrophe in blackbody radiation. Calculate energy of quanta using Planck s equation.

Explain how Planck resolved the ultraviolet catastrophe in blackbody radiation. Calculate energy of quanta using Planck s equation. Objectives Explain how Planck resolved the ultraviolet catastrophe in blackbody radiation. Calculate energy of quanta using Planck s equation. Solve problems involving maximum kinetic energy, work function,

More information

Modern Physics for Scientists and Engineers International Edition, 4th Edition

Modern Physics for Scientists and Engineers International Edition, 4th Edition Modern Physics for Scientists and Engineers International Edition, 4th Edition http://optics.hanyang.ac.kr/~shsong Review: 1. THE BIRTH OF MODERN PHYSICS 2. SPECIAL THEORY OF RELATIVITY 3. THE EXPERIMENTAL

More information

Blackbody radiation The photoelectric effect Compton effect Line spectra Nuclear physics/bohr model Lasers Quantum mechanics

Blackbody radiation The photoelectric effect Compton effect Line spectra Nuclear physics/bohr model Lasers Quantum mechanics Blackbody radiation The photoelectric effect Compton effect Line spectra Nuclear physics/bohr model Lasers Quantum mechanics Phys 2435: Chap. 38, Pg 1 Blackbody radiation New Topic Phys 2435: Chap. 38,

More information

Chapter 27 Early Quantum Theory and Models of the Atom

Chapter 27 Early Quantum Theory and Models of the Atom Chapter 27 Early Quantum Theory and Models of the Atom Modern Physics 19th century physics had so many great successes, that most people felt nature was almost fully understood. Just a few small clouds

More information

College Physics B - PHY2054C

College Physics B - PHY2054C of College - PHY2054C The of 11/17/2014 My Office Hours: Tuesday 10:00 AM - Noon 206 Keen Building Outline of 1 2 of 3 4 of Puzzling The blackbody intensity falls to zero at both long and short wavelengths,

More information

Chapter 38. Photons Light Waves Behaving as Particles

Chapter 38. Photons Light Waves Behaving as Particles Chapter 38 Photons Light Waves Behaving as Particles 38.1 The Photoelectric Effect The photoelectric effect was first discovered by Hertz in 1887, and was explained by Einstein in 1905. The photoelectric

More information

Lecture PowerPoints. Chapter 27 Physics: Principles with Applications, 7th edition Giancoli

Lecture PowerPoints. Chapter 27 Physics: Principles with Applications, 7th edition Giancoli Lecture PowerPoints Chapter 27 Physics: Principles with Applications, 7th edition Giancoli This work is protected by United States copyright laws and is provided solely for the use of instructors in teaching

More information

General Physics (PHY 2140) Lecture 15

General Physics (PHY 2140) Lecture 15 General Physics (PHY 2140) Lecture 15 Modern Physics Chapter 27 1. Quantum Physics The Compton Effect Photons and EM Waves Wave Properties of Particles Wave Functions The Uncertainty Principle http://www.physics.wayne.edu/~alan/2140website/main.htm

More information

E n = n h ν. The oscillators must absorb or emit energy in discrete multiples of the fundamental quantum of energy given by.

E n = n h ν. The oscillators must absorb or emit energy in discrete multiples of the fundamental quantum of energy given by. Planck s s Radiation Law Planck made two modifications to the classical theory The oscillators (of electromagnetic origin) can only have certain discrete energies determined by E n = n h ν with n is an

More information

IB Physics SL Y2 Option B (Quantum and Nuclear Physics) Exam Study Guide Practice Problem Solutions

IB Physics SL Y2 Option B (Quantum and Nuclear Physics) Exam Study Guide Practice Problem Solutions IB Physics SL Y2 Option B (Quantum and Nuclear Physics) Exam Study Guide Practice Problem Solutions Objectives: 1. Describe the photoelectric effect. (B.1.1) 2. Describe the concept of the photon and use

More information

The Atom and Quantum Mechanics

The Atom and Quantum Mechanics The Atom and Quantum Mechanics Last time... In a spherical geometry the sum of the angles of a triangle > 180 What is the principle of equivalence? What three observations confirmed Einstein s Theory of

More information

Chapter 7. The Quantum Mechanical Model of the Atom

Chapter 7. The Quantum Mechanical Model of the Atom Chapter 7 The Quantum Mechanical Model of the Atom The Nature of Light:Its Wave Nature Light is a form of electromagnetic radiation composed of perpendicular oscillating waves, one for the electric field

More information

Semiconductor Physics and Devices

Semiconductor Physics and Devices Introduction to Quantum Mechanics In order to understand the current-voltage characteristics, we need some knowledge of electron behavior in semiconductor when the electron is subjected to various potential

More information

Chapter 28: Quantum Physics. Don t Copy This. Quantum Physics 3/16/13

Chapter 28: Quantum Physics. Don t Copy This. Quantum Physics 3/16/13 Chapter 28: Quantum Physics Key Terms: Photoelectric effect Photons de Broglie wavelength Energy level diagram Wave-particle duality Don t Copy This Except for relativity, everything we have studied up

More information

Particle Wave Duality. What is a particle? What is a wave?

Particle Wave Duality. What is a particle? What is a wave? Particle Wave Duality What is a particle? What is a wave? Problems with Classical Physics Nature of Light? Discrete Spectra? Blackbody Radiation? Photoelectric Effect? Compton Effect? Model of Atom? Thomas

More information

Photoelectric Effect [20 marks]

Photoelectric Effect [20 marks] Photoelectric Effect [20 marks] 1. photoelectric cell is connected in series with a battery of emf 2 V. Photons of energy 6 ev are incident on the cathode of the photoelectric cell. The work function of

More information

The Photoelectric Effect

The Photoelectric Effect The Photoelectric Effect Light can strike the surface of some metals causing an electron to be ejected No matter how brightly the light shines, electrons are ejected only if the light has sufficient energy

More information

SECTION A Quantum Physics and Atom Models

SECTION A Quantum Physics and Atom Models AP Physics Multiple Choice Practice Modern Physics SECTION A Quantum Physics and Atom Models 1. Light of a single frequency falls on a photoelectric material but no electrons are emitted. Electrons may

More information

Alan Mortimer PhD. Ideas of Modern Physics

Alan Mortimer PhD. Ideas of Modern Physics Alan Mortimer PhD Ideas of Modern Physics Electromagnetic Waves Last Week Special Relativity General Relativity The Quantum World Index Planck s Law Atomic Structure and emission lines Matter waves Uncertainty

More information

Physics 1C. Modern Physics Lecture

Physics 1C. Modern Physics Lecture Physics 1C Modern Physics Lecture "I ask you to look both ways. For the road to a knowledge of the stars leads through the atom; and important knowledge of the atom has been reached through the stars."

More information

Chap. 3. Elementary Quantum Physics

Chap. 3. Elementary Quantum Physics Chap. 3. Elementary Quantum Physics 3.1 Photons - Light: e.m "waves" - interference, diffraction, refraction, reflection with y E y Velocity = c Direction of Propagation z B z Fig. 3.1: The classical view

More information

Energy levels and atomic structures lectures chapter one

Energy levels and atomic structures lectures chapter one Structure of Atom An atom is the smallest constituent unit of ordinary matter that has the properties of a element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are

More information

Chapter 27 Early Quantum Theory and Models of the Atom Discovery and Properties of the electron

Chapter 27 Early Quantum Theory and Models of the Atom Discovery and Properties of the electron Chapter 27 Early Quantum Theory and Models of the Atom 27-1 Discovery and Properties of the electron Measure charge to mass ratio e/m (J. J. Thomson, 1897) When apply magnetic field only, the rays are

More information

Chapter 29 Atomic Physics. Looking Ahead. Slide 29-1

Chapter 29 Atomic Physics. Looking Ahead. Slide 29-1 Chapter 29 Atomic Physics Looking Ahead Slide 29-1 Atomic Spectra and the Bohr Model In the mid 1800s it became apparent that the spectra of atomic gases is comprised of individual emission lines. Slide

More information

Physics 102: Lecture 24. Bohr vs. Correct Model of Atom. Physics 102: Lecture 24, Slide 1

Physics 102: Lecture 24. Bohr vs. Correct Model of Atom. Physics 102: Lecture 24, Slide 1 Physics 102: Lecture 24 Bohr vs. Correct Model of Atom Physics 102: Lecture 24, Slide 1 Plum Pudding Early Model for Atom positive and negative charges uniformly distributed throughout the atom like plums

More information

Chapter 28. Atomic Physics

Chapter 28. Atomic Physics Chapter 28 Atomic Physics Sir Joseph John Thomson J. J. Thomson 1856-1940 Discovered the electron Did extensive work with cathode ray deflections 1906 Nobel Prize for discovery of electron Early Models

More information

Chapter 1. From Classical to Quantum Mechanics

Chapter 1. From Classical to Quantum Mechanics Chapter 1. From Classical to Quantum Mechanics Classical Mechanics (Newton): It describes the motion of a classical particle (discrete object). dp F ma, p = m = dt dx m dt F: force (N) a: acceleration

More information

Chapter 27 Lecture Notes

Chapter 27 Lecture Notes Chapter 27 Lecture Notes Physics 2424 - Strauss Formulas: λ P T = 2.80 10-3 m K E = nhf = nhc/λ fλ = c hf = K max + W 0 λ = h/p λ - λ = (h/mc)(1 - cosθ) 1/λ = R(1/n 2 f - 1/n 2 i ) Lyman Series n f = 1,

More information

Learning Objectives and Worksheet I. Chemistry 1B-AL Fall 2016

Learning Objectives and Worksheet I. Chemistry 1B-AL Fall 2016 Learning Objectives and Worksheet I Chemistry 1B-AL Fall 2016 Lectures (1 2) Nature of Light and Matter, Quantization of Energy, and the Wave Particle Duality Read: Chapter 12, Pages: 524 526 Supplementary

More information

Physics 1C. Chapter 28 !!!!

Physics 1C. Chapter 28 !!!! Physics 1C Chapter 28!!!! "Splitting the atom is like trying to shoot a gnat in the Albert Hall at night and using ten million rounds of ammunition on the off chance of getting it. That should convince

More information

Unknown X -Rays:high penetration

Unknown X -Rays:high penetration The nobel prize in physics 1901 Wilhelm Conrad Röntgen Germany in recognition of the extraordinary services he has rendered by the discovery of the remarkable rays subsequently named after him" Discovery

More information

Physics 126 Practice Exam #4 Professor Siegel

Physics 126 Practice Exam #4 Professor Siegel Physics 126 Practice Exam #4 Professor Siegel Name: Lab Day: 1. Light is usually thought of as wave-like in nature and electrons as particle-like. In which one of the following instances does light behave

More information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) In the equation E = hf, the f stands for 1) A) the smaller wavelengths of visible light. B) wave

More information

Chapter 10: Wave Properties of Particles

Chapter 10: Wave Properties of Particles Chapter 10: Wave Properties of Particles Particles such as electrons may demonstrate wave properties under certain conditions. The electron microscope uses these properties to produce magnified images

More information

COLLEGE PHYSICS. Chapter 30 ATOMIC PHYSICS

COLLEGE PHYSICS. Chapter 30 ATOMIC PHYSICS COLLEGE PHYSICS Chapter 30 ATOMIC PHYSICS Matter Waves: The de Broglie Hypothesis The momentum of a photon is given by: The de Broglie hypothesis is that particles also have wavelengths, given by: Matter

More information

The Atom. Result for Hydrogen. For example: the emission spectrum of Hydrogen: Screen. light. Hydrogen gas. Diffraction grating (or prism)

The Atom. Result for Hydrogen. For example: the emission spectrum of Hydrogen: Screen. light. Hydrogen gas. Diffraction grating (or prism) The Atom What was know about the atom in 1900? First, the existence of atoms was not universally accepted at this time, but for those who did think atoms existed, they knew: 1. Atoms are small, but they

More information

Quantum Mechanics. Physics April 2002 Lecture 9. Planck Bohr Schroedinger Heisenberg

Quantum Mechanics. Physics April 2002 Lecture 9. Planck Bohr Schroedinger Heisenberg Quantum Mechanics Physics 102 18 April 2002 Lecture 9 Planck Bohr Schroedinger Heisenberg From: http://www.th.physik.uni-frankfurt.de/~jr/portraits.html 18 Apr 2002 Physics 102 Lecture 9 1 Blackbody radiation

More information

Introduction to Quantum Physics. Early Atomic Physics

Introduction to Quantum Physics. Early Atomic Physics Introduction to Quantum Physics Early Atomic Physics What is Quantum Physics Quantum Physics is a collection of laws which explain observations of the tiny building blocks of all matter. The world of the

More information

LIGHT. Question. Until very recently, the study of ALL astronomical objects, outside of the Solar System, has been with telescopes observing light.

LIGHT. Question. Until very recently, the study of ALL astronomical objects, outside of the Solar System, has been with telescopes observing light. LIGHT Question Until very recently, the study of ALL astronomical objects, outside of the Solar System, has been with telescopes observing light. What kind of information can we get from light? 1 Light

More information

LECTURE 23 SPECTROSCOPY AND ATOMIC MODELS. Instructor: Kazumi Tolich

LECTURE 23 SPECTROSCOPY AND ATOMIC MODELS. Instructor: Kazumi Tolich LECTURE 23 SPECTROSCOPY AND ATOMIC MODELS Instructor: Kazumi Tolich Lecture 23 2 29.1 Spectroscopy 29.2 Atoms The first nuclear physics experiment Using the nuclear model 29.3 Bohr s model of atomic quantization

More information

Chapter 6 Electronic structure of atoms

Chapter 6 Electronic structure of atoms Chapter 6 Electronic structure of atoms light photons spectra Heisenberg s uncertainty principle atomic orbitals electron configurations the periodic table 6.1 The wave nature of light Visible light is

More information

like firing a 16 shell at a piece of tissue paper and seeing it bounce back. - E Rutherford

like firing a 16 shell at a piece of tissue paper and seeing it bounce back. - E Rutherford Black body radiation [const.] λ max = T E radiated surf. area Planck E f hf = T E W KE 4 ROY G BIV Einstein Photo-electric effect- Photons Thompson electron identification B + F v R +q 2 mv F= =qvb=f R

More information

U n 3 n Ba Kr (D) Br (C) Kr (B) Rb (E) 94 37

U n 3 n Ba Kr (D) Br (C) Kr (B) Rb (E) 94 37 1984 36. The critical angle for a transparent material in air is 30. The index of refraction of the material is most nearly (A) 0.33 (B) 0.50 (C) 1.0 (D) 1.5 (E) 2.0 37. An object is placed as shown in

More information

We also find the development of famous Schrodinger equation to describe the quantization of energy levels of atoms.

We also find the development of famous Schrodinger equation to describe the quantization of energy levels of atoms. Lecture 4 TITLE: Quantization of radiation and matter: Wave-Particle duality Objectives In this lecture, we will discuss the development of quantization of matter and light. We will understand the need

More information

Physics 1C Lecture 28C. "For those who are not shocked when they first come across quantum theory cannot possibly have understood it.

Physics 1C Lecture 28C. For those who are not shocked when they first come across quantum theory cannot possibly have understood it. Physics 1C Lecture 28C "For those who are not shocked when they first come across quantum theory cannot possibly have understood it." --Neils Bohr Outline CAPE and extra credit problems Wave-particle duality

More information

CHEMISTRY Matter and Change

CHEMISTRY Matter and Change CHEMISTRY Matter and Change Chapter 5: Electrons in Atoms 5 Section 5.1 Section Section 5.3 Table Of Contents Light and Quantized Energy Electron Configuration Compare the wave and particle natures of

More information

Chapter One. The Old Quantum Theory. 1-1 Why Quantum Mechanics.

Chapter One. The Old Quantum Theory. 1-1 Why Quantum Mechanics. Chapter One The Old Quantum Theory 1-1 Why Quantum Mechanics. The birth of quantum mechanics can be dated to 1925, when physicists such as Werner Heisenberg and Erwin Schrödinger invented mathematical

More information

Modern Physics. Light as a Particle

Modern Physics. Light as a Particle Day 1 Modern Physics NOTE: each topic is sectioned into days numbered from 1 to 7. This would be a good pace to follow as you make your way through the unit. If you learn one section per day, you will

More information

5.111 Lecture Summary #4 Wednesday, September 10, 2014

5.111 Lecture Summary #4 Wednesday, September 10, 2014 5.111 Lecture Summary #4 Wednesday, September 10, 2014 Reading for today: Section 1.5 and Section 1.6. (Same sections in 5 th and 4 th editions) Read for Lecture #5: Section 1.3 Atomic Spectra, Section

More information

Franck-Hertz experiment, Bohr atom, de Broglie waves Announcements:

Franck-Hertz experiment, Bohr atom, de Broglie waves Announcements: Franck-Hertz experiment, Bohr atom, de Broglie waves Announcements: Problem solving sessions Tues. 1-3. Reading for Wednesday TZD 6.1-.4 2013 Nobel Prize Announcement Tomorrow Few slides on the Higgs Field

More information

The Photoelectric Effect

The Photoelectric Effect Stellar Astrophysics: The Interaction of Light and Matter The Photoelectric Effect Methods of electron emission Thermionic emission: Application of heat allows electrons to gain enough energy to escape

More information

Experimental Basis for QM Ch3

Experimental Basis for QM Ch3 Experimental Basis for QM Ch3 This chapter describes the early evidence for quantization including Blackbody radiation Photoelectric effect Compton scattering X-rays and their spectra We ll see how early

More information

LECTURE 6 QUANTUM PHYSICS II. Instructor: Shih-Chieh Hsu

LECTURE 6 QUANTUM PHYSICS II. Instructor: Shih-Chieh Hsu LECTURE 6 QUANTUM PHYSICS II Instructor: Shih-Chieh Hsu Development of Quantum Mechanics 2 In 1862, Kirchhoff coined black body radiation or known as cavity radiation The experiments raised the question

More information

Exam 2 Development of Quantum Mechanics

Exam 2 Development of Quantum Mechanics PHYS420 (Spring 2002) Riq Parra Exam #2 (Friday, April 12 th, 2002) Exam 2 Development of Quantum Mechanics Do NOT write your name on this exam. Write your class ID number on the top right hand corner

More information

CHAPTER 28 Quantum Mechanics of Atoms Units

CHAPTER 28 Quantum Mechanics of Atoms Units CHAPTER 28 Quantum Mechanics of Atoms Units Quantum Mechanics A New Theory The Wave Function and Its Interpretation; the Double-Slit Experiment The Heisenberg Uncertainty Principle Philosophic Implications;

More information

Atomic Spectra. What does this have to do with atomic models?

Atomic Spectra. What does this have to do with atomic models? Atomic Physics -2 Atomic Spectra Fill a glass tube with pure atomic gas Apply a high voltage between electrodes Current flows through gas & tube glows Color depends on type of gas Light emitted is composed

More information

Electrons in Atoms. Section 5.1 Light and Quantized Energy Section 5.2 Quantum Theory and the Atom Section 5.3 Electron Configuration

Electrons in Atoms. Section 5.1 Light and Quantized Energy Section 5.2 Quantum Theory and the Atom Section 5.3 Electron Configuration Electrons in Atoms Section 5.1 Light and Quantized Energy Section 5.2 Quantum Theory and the Atom Section 5.3 Electron Configuration Click a hyperlink or folder tab to view the corresponding slides. Exit

More information

Review & Summary. Barrier tunneling by matter wave. Sample Problem 38.06

Review & Summary. Barrier tunneling by matter wave. Sample Problem 38.06 REVIEW & SUMMARY 79 Sample Problem 8.06 Barrier tunneling by matter wave Suppose that the electron in Fig. 8-7, having a total energy E of 5. ev, approaches a barrier of height U b 6.8 ev and thickness

More information

Complementi di Fisica Lectures 7-9

Complementi di Fisica Lectures 7-9 Complementi di Fisica Lectures 7-9 Livio Lanceri Università di Trieste Trieste, 07/09-10-2012 Course Outline - Reminder Quantum Mechanics: an introduction Waves as particles and particles as waves (the

More information