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

Size: px
Start display at page:

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

Transcription

1 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 their courses and assessing student learning. Dissemination or sale of any part of this work (including on the World Wide Web) will destroy the integrity of the work and is not permitted. The work and materials from it should never be made available to students except by instructors using the accompanying text in their classes. All recipients of this work are expected to abide by these restrictions and to honor the intended pedagogical purposes and the needs of other instructors who rely on these materials.

2 Chapter 27 Early Quantum Theory and Models of the Atom

3 Contents of Chapter 27 Discovery and Properties of the Electron Blackbody Radiation; Planck s Quantum Hypothesis Photon Theory of Light and the Photoelectric Effect Energy, Mass, and Momentum of a Photon Compton Effect Photon Interactions; Pair Production

4 Contents of Chapter 27 Wave-Particle Duality; the Principle of Complementarity Wave Nature of Matter Electron Microscopes Early Models of the Atom Atomic Spectra: Key to the Structure of the Atom The Bohr Model de Broglie s Hypothesis Applied to Atoms

5 27-1 Discovery and Properties of the Electron In the late 19 th century, discharge tubes were made that emitted cathode rays. These rays are emitted at the cathode, or negative terminal. In 1879 Crookes had proposed that the cathode rays were 'radiant matter', negatively charged particles that were repelled from the negatively charged cathode and attracted to the positively charged anode. The nature of the cathode rays was controversial. Although Thomson thought the rays must be particles, many Europeans thought they were waves. In Germany Hertz had observed the rays passing through thin sheets of gold. It seemed impossible that particles could pass through solid matter.

6 27-1 Discovery and Properties of the Electron J.J. Thomson realized that he could deflect the cathode rays in an electric field produced by a pair of metal plates. One of the plates was negatively charged, while the other was positively charged. The cathode rays moved towards the positively charged plate so the rays must be negatively charged. A current in a coil of wire produces a magnetic field. Two coils will produce a uniform magnetic field. A beam of charged particles passing through the magnetic field will be bent. The magnetic field produces a force which deflects the cathode rays. Thomson positioned the coils so that the deflection was in the opposite direction to the deflection produced by the electric field. By adjusting the strengths of the fields the rays could be deflected, in one direction by the electric field, and back an equal amount by the magnetic field. The forces were balanced.

7 27-1 Discovery and Properties of the Electron By accelerating the rays through a known potential and then measuring the radius of their path in a known magnetic field, the charge to mass ratio could be measured: The result is e/m = C/kg. (27-1)

8 27-1 Discovery and Properties of the Electron Cathode rays were soon called electrons. Millikan devised an experiment to measure the charge on the electron by measuring the electric field needed to suspend an oil droplet of known mass between parallel plates.

9 27-1 Discovery and Properties of the Electron The mass and charge of each droplet were measured; careful analysis of the data showed that the charge was always an integral multiple of a smallest charge, e.

10 27-1 Discovery and Properties of the Electron The currently accepted value of e is: e = C Knowing e allows the electron mass to be calculated: m e = kg

11 27-2 Blackbody Radiation; Planck s Quantum Hypothesis We shall now turn to another puzzle confronting physicists at the turn of the century (1900): just how do heated bodies radiate? There was a general understanding of the mechanism involved heat was known to cause the molecules and atoms of a solid to vibrate. What is meant by the phrase black body radiation? The point is that the radiation from a heated body depends to some extent on the body being heated. All objects emit radiation whose total intensity is proportional to the fourth power of their temperature. This is called thermal radiation; a blackbody is an object that emits thermal radiation only. The spectrum of blackbody radiation has been measured; it is found that the frequency of peak intensity increases linearly with temperature.

12 27-2 Blackbody Radiation; Planck s Quantum Hypothesis This figure shows blackbody radiation curves for three different temperatures. Note that frequency increases to the left.

13 27-2 Blackbody Radiation; Planck s Quantum Hypothesis This spectrum could not be reproduced using19 th -century physics. A solution was proposed by Max Planck in 1900: The energy of atomic oscillations within atoms cannot have an arbitrary value; it is related to the frequency: E = hf The constant h is now called Planck s constant. The smallest amount of energy possible hf is called the quantum of energy

14 27-2 Blackbody Radiation; Planck s Quantum Hypothesis Planck found the value of his constant by fitting blackbody curves: h = J s Planck s proposal was that the energy of an oscillation had to be an integral multiple of hf. This is called the quantization of energy.

15 Example Estimate the peal wavelength of light emitted from the pupil of the human eye assuming normal body temperature (~37 C). Solution: T = = 310 K. λ P T = m K λ P = m K 310K = m

16 27-3 Photon Theory of Light and the Photoelectric Effect Einstein suggested that, given the success of Planck s theory, light must exist as a set of small energy packets: (27-4) These tiny packets, or particles, are called photons.

17 27-3 Photon Theory of Light and the Photoelectric Effect The photoelectric effect: If light strikes a metal, electrons are emitted. The effect does not occur if the frequency of the light is too low; the kinetic energy of the electrons increases with frequency.

18 27-3 Photon Theory of Light and the Photoelectric Effect If light is a wave, theory predicts for the photoelectric effect: 1. Number of electrons and their energy should increase with intensity 2. Frequency should not matter

19 27-3 Photon Theory of Light and the Photoelectric Effect If light is particles (photons), theory predicts for the photoelectric effect: Increasing intensity increases number of electrons but not energy Above a minimum energy required to break atomic bond, kinetic energy will increase linearly with frequency There is a cutoff frequency below which no electrons will be emitted, regardless of intensity

20 27-3 Photon Theory of Light and the Photoelectric Effect The particle theory assumes that an electron absorbs a single photon. Plotting the kinetic energy vs. frequency: This shows clear agreement with the particle theory of light, not wave theory

21 27-3 Photon Theory of Light and the Photoelectric Effect The photoelectric effect is how electric eye detectors work. It is also used for movie film soundtracks.

22 27-4 Energy, Mass, and Momentum of a Photon Photons must travel at the speed of light. Looking at the relativistic equation for momentum, it is clear that this can only happen if its rest mass is zero. We already know that the energy is hf; we can put this in the relativistic energy-momentum relation and find the momentum: (27-6)

23 Example About 0.1 ev is necessary to break a hydrogen bond in a protein molecule. Calculate the minimum frequency and maximum wavelength of a photon that can do this. Solution: E min = hf min f min = E min h λ max = c f min = 0.1 ev J / ev J s = m / s Hz = m = Hz;

24 27-5 Compton Effect Compton did experiments in which he scattered X-rays from different materials. He found that the scattered X-rays had a slightly longer wavelength than the incident ones, and that the wavelength depended on the scattering angle: (27-7)

25 27-6 Photon Interactions; Pair Production Photons passing through matter can undergo the following interactions: 1. Photoelectric effect: photon is completely absorbed, electron is ejected 2. Photon may be totally absorbed by electron, but not have enough energy to eject it; the electron moves into an excited state 3. The photon can scatter from an atom and lose some energy 4. The photon can produce an electron-positron pair.

26 27-6 Photon Interactions; Pair Production In pair production, energy, electric charge, and momentum must all be conserved. Energy will be conserved through the mass and kinetic energy of the electron and positron; their opposite charges conserve charge; and the interaction must take place in the electromagnetic field of a nucleus, which can contribute momentum.

27 We have phenomena such as diffraction and interference that show that light is a wave, and phenomena such as the photoelectric effect and the Compton effect that show that it is a particle. Which is it? 27-7 Wave-Particle Duality; the Principle of Complementarity This question has no answer; we must accept the dual waveparticle nature of light. The principle of complementarity states that both the wave and particle aspects of light are fundamental to its nature. Indeed, waves and particles are just our interpretation of how light behaves.

28 27-8 Wave Nature of Matter Just as light sometimes behaves as a particle, matter sometimes behaves like a wave. The wavelength of a particle of matter is: (27-8) This wavelength is extraordinarily small for most objects. The wave nature of matter becomes more important for very light particles such as the electron.

29 Example 2 Visible light incident on a diffraction grating with slot spacing of 0.01mm has the first maximum at an angle of 3.6 from the central peak. If electrons could be diffracted by the same grating, what electron velocity would produce the same diffraction pattern as the visible light? Solution: First maximum means that we have constructive interference here: d sinθ = nλ λ = d sinθ n v = hn md sinθ = = h p = h mv ( J s) kg ( )( m) sin 3.6 ( ) =1159 m / s

30 27-8 Wave Nature of Matter Electron wavelengths can easily be on the order of m; electrons can be diffracted by crystals just as X-rays can.

31 Examples (1) Calculate the wavelength of a 0.21-kg ball traveling at 0.1 m/s. Solution: λ = h p = h mv = J s 0.21kg ( ) 0.1m / s ( ) = m Extremely small! Cannot detect it at all in everyday s life. (2) What is the wavelength of an electron (m= kg) traveling at m/s? λ = h p = h mv = J s ( kg) m / s ( ) = m Waves with such wavelength can be observed in diffraction experiments

32 27-9 Electron Microscopes The wavelength of electrons will vary with energy, but is still quite short. This makes electrons useful for imaging remember that the smallest object that can be resolved is about one wavelength. Electrons used in electron microscopes have wavelengths of about nm. Example: What voltage is needed to produce electron wavelength of 0.06 nm? Solution: The kinetic energy is acquired by electrostatic potential energy. KE = mv 2 2 = p2 2m ; p = h λ KE = h 2 2mλ 2 KE = ev electron is accerated by electric field ( ) h 2 2mλ 2 = ev V = h 2 2meλ 2 = kg ( J s) 2 ( )( C) ( m) = 419 V 2

33 27-9 Electron Microscopes Transmission electron microscope the electrons are focused by magnetic coils

34 27-9 Electron Microscopes Scanning electron microscope the electron beam is scanned back and forth across the object to be imaged

35 27-9 Electron Microscopes Scanning tunneling microscope up and down motion of the probe keeps the current constant. surface. Plotting that motion produces an image of the

36 27-10 Early Models of the Atom It was known in the late 19 th century that atoms were electrically neutral, but that they could become charged, implying that there were positive and negative charges and that some of them could be removed. One popular atomic model was the plum-pudding model. This model had the atom consisting of a bulk positive charge, with negative electrons buried throughout.

37 27-10 Early Models of the Atom Around 1911, Rutherford did an experiment that showed that the positively charged nucleus must be extremely small compared to the rest of the atom. He scattered alpha particles helium nuclei from a metal foil and observed the scattering angle. He found that some of the angles were far larger than the plum-pudding model would allow.

38 27-10 Early Models of the Atom The only way to account for the large angles was to assume that all the positive charge was contained within a tiny volume. Therefore, Rutherford s model of the atom is mostly empty space: Now we know that the radius of the nucleus is 1/10000 that of the atom.

39 27-11 Atomic Spectra: Key to the Structure of the Atom A very thin gas heated in a discharge tube emits light only at characteristic frequencies.

40 27-11 Atomic Spectra: Key to the Structure of the Atom An atomic spectrum is a line spectrum only certain frequencies appear. If white light passes through such a gas, it absorbs at those same frequencies.

41 27-11 Atomic Spectra: Key to the Structure of the Atom The wavelengths of electrons emitted from hydrogen have a regular pattern: (27-9) This is called the Balmer series. R is the Rydberg constant: R = m 1

42 27-11 Atomic Spectra: Key to the Structure of the Atom Other series include the Lyman series: And the Paschen series:

43 27-11 Atomic Spectra: Key to the Structure of the Atom A portion of the complete spectrum of hydrogen is shown here. The lines cannot be explained by the Rutherford theory.

44 27-12 The Bohr Atom Bohr proposed that the possible energy states for atomic electrons were quantized only certain values were possible. Then the spectrum could be explained as transitions from one level to another.

45 27-12 The Bohr Atom Bohr found that the angular momentum was quantized: (27-11)

46 27-12 The Bohr Atom An electron is held in orbit by the Coulomb force:

47 27-12 The Bohr Atom Using the Coulomb force, we can calculate the radii of the orbits: (27-12)

48 27-12 The Bohr Atom The lowest energy level is called the ground state; the others are excited states. Bohr assumed that electrons in fixed orbits do not radiate light. He was not able to say how an electron moved when it made a transition from one energy level to another. The idea of electron orbits was rejected. Today electrons are thought as forming probability clouds.

49 Electrons accelerated from rest by a potential difference of 12.3 V pass through a gas of hydrogen atoms at room temperature. What wavelengths of light will be emitted? Solution: the potential difference gives the electrons a kinetic energy of 12.3 ev, so it is possible to provide this much energy to the hydrogen atom through collisions. From the ground state, the maximum Example energy of the atom is ev ev = 1.3 ev. From the energy level diagram, we see that this means that the atom could be excited to the n = 3 state, so the possible transitions when the atom returns to the ground state are n=3 to n=2, n=3 to n=1, and n=2 to n=1.

50 Example (continued) So we will calculate the wavelengths using equation 1 λ = 1 ( hc E E ) n n 1 h = ev s; c = m / s λ 3 1 = λ 2 1 = λ 3 2 = hc E 3 E 1 = hc E 2 E 1 = hc E 3 E 2 = 1240eV nm [ 1.5eV ( 13.6eV )] 1240eV nm [ 3.4eV ( 13.6eV )] =102 nm =122 nm 1240eV nm = 650 nm [ 1.5eV ( 3.4eV )]

51 27-12 The Bohr Atom The correspondence principle applies here as well when the differences between quantum levels are small compared to the energies, they should be imperceptible. Correspondence principle means that when you move from quantum world to macro-world, the theory must be able to predict classical results.

52 27-13 de Broglie s Hypothesis Applied to Atoms De Broglie s hypothesis is the one associating a wavelength with the momentum of a particle. He proposed that only those orbits where the wave would be a circular standing wave will occur. This yields the same relation that Bohr had proposed. In addition, it makes more reasonable the fact that the electrons do not radiate, as one would otherwise expect from an accelerating charge..

53 27-13 de Broglie s Hypothesis Applied to Atoms De Broglie argued that the electron wave was a circular standing wave that closes on itself. If this does not happen, destructive interference takes place as the wave travels around the loop, and the wave quickly dies out. For constructive interference we need 2πr n =nλ; λ=h/mv mvr n =nh/(2π) exactly what Bohr proposed! These are circular standing waves for n = 2, 3, and 5.

54 Example 3 Construct the energy-level diagram for doubly ionized lithium, Li 2+. Solution: Lithium nucleus has 3 protons (positively charged particles), so Z=3. Energy levels are given as E n = ( 13.6 ev ) Z 2 n 2 = ( 13.6 ev ) 32 ev 2 = n n 2 E 1 = ev ; E 2 = 30.6 ev ; E 3 = 13.6 ev ;

55 Summary of Chapter 27 Planck s hypothesis: molecular oscillation energies are quantized Light can be considered to consist of photons, each of energy Photoelectric effect: incident photons knock electrons out of material

56 Summary of Chapter 27 Compton effect and pair production also support photon theory Wave-particle duality both light and matter have both wave and particle properties Wavelength of an object with mass:

57 Summary of Chapter 27 Principle of complementarity: both wave and particle properties are necessary for complete understanding Rutherford showed that atom has tiny nucleus Line spectra are explained by electrons having only certain specific orbits Ground state has the lowest energy; the others are called excited states

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

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

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 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

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

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

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

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

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

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

Physics 1C Lecture 29A. Finish off Ch. 28 Start Ch. 29

Physics 1C Lecture 29A. Finish off Ch. 28 Start Ch. 29 Physics 1C Lecture 29A Finish off Ch. 28 Start Ch. 29 Particle in a Box Let s consider a particle confined to a one-dimensional region in space. Following the quantum mechanics approach, we need to find

More information

Early Quantum Theory and Models of the Atom

Early Quantum Theory and Models of the Atom Early Quantum Theory and Models of the Atom Electron Discharge tube (circa 1900 s) There is something ( cathode rays ) which is emitted by the cathode and causes glowing Unlike light, these rays are deflected

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

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

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

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

Atom Physics. Chapter 30. DR JJ UiTM-Cutnell & Johnson 7th ed. 1. Model of an atom-the recent model. Nuclear radius r m

Atom Physics. Chapter 30. DR JJ UiTM-Cutnell & Johnson 7th ed. 1. Model of an atom-the recent model. Nuclear radius r m Chapter 30 Atom Physics DR JJ UiTM-Cutnell & Johnson 7th ed. 1 30.1 Rutherford Scattering and the Nuclear Atom Model of an atom-the recent model Nuclear radius r 10-15 m Electron s position radius r 10-10

More information

DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS

DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS DEVIL PHYSICS THE BADDEST CLASS ON CAMPUS IB PHYSICS LSN 12-1A: INTERACTIONS OF MATTER WITH RADIATION Questions From Reading Activity? Essential Idea: The microscopic quantum world offers a range of phenomena,

More information

Professor K. Atomic structure

Professor K. Atomic structure Professor K Atomic structure Review Reaction- the formation and breaking of chemical bonds Bond- a transfer or sharing of electrons Electrons Abbreviated e - What are they? How were they discovered? Early

More information

Particle Detectors and Quantum Physics (2) Stefan Westerhoff Columbia University NYSPT Summer Institute 2002

Particle Detectors and Quantum Physics (2) Stefan Westerhoff Columbia University NYSPT Summer Institute 2002 Particle Detectors and Quantum Physics (2) Stefan Westerhoff Columbia University NYSPT Summer Institute 2002 More Quantum Physics We know now how to detect light (or photons) One possibility to detect

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

Radiation - Electromagnetic Waves (EMR): wave consisting of oscillating electric and magnetic fields that move at the speed of light through space.

Radiation - Electromagnetic Waves (EMR): wave consisting of oscillating electric and magnetic fields that move at the speed of light through space. Radiation - Electromagnetic Waves (EMR): wave consisting of oscillating electric and magnetic fields that move at the speed of light through space. Photon: a quantum of light or electromagnetic wave. Quantum:

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

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

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

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

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

Atomic Structure-Notes

Atomic Structure-Notes Subatomic Particles Electron, proton and neutron Atomic Structure-Notes Discovery of Electron (Michael Faraday s Cathode Ray Discharge Tube Experiment) Experimental Setup: Glass tube is partially evacuated

More information

Discovery of the Atomic Nucleus. Conceptual Physics 11 th Edition. Discovery of the Electron. Discovery of the Atomic Nucleus

Discovery of the Atomic Nucleus. Conceptual Physics 11 th Edition. Discovery of the Electron. Discovery of the Atomic Nucleus Conceptual Physics 11 th Edition Chapter 32: THE ATOM AND THE QUANTUM Discovery of the Atomic Nucleus These alpha particles must have hit something relatively massive but what? Rutherford reasoned that

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

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 31 Atomic Physics

Chapter 31 Atomic Physics 100 92 86 100 92 84 100 92 84 98 92 83 97 92 82 96 91 80 96 91 76 95 91 74 95 90 68 95 89 67 95 89 66 94 87 93 86 No. of Students in Range Exam 3 Score Distribution 25 22 20 15 10 10 5 3 2 0 0 0 0 0 0

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

Chapters 31 Atomic Physics

Chapters 31 Atomic Physics Chapters 31 Atomic Physics 1 Overview of Chapter 31 Early Models of the Atom The Spectrum of Atomic Hydrogen Bohr s Model of the Hydrogen Atom de Broglie Waves and the Bohr Model The Quantum Mechanical

More information

Quantum theory and models of the atom

Quantum theory and models of the atom Guess now. It has been found experimentally that: (a) light behaves as a wave; (b) light behaves as a particle; (c) electrons behave as particles; (d) electrons behave as waves; (e) all of the above are

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

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

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

General Physics (PHY 2140)

General Physics (PHY 2140) General Physics (PHY 140) Lecture 33 Modern Physics Atomic Physics Atomic spectra Bohr s theory of hydrogen http://www.physics.wayne.edu/~apetrov/phy140/ Chapter 8 1 Lightning Review Last lecture: 1. Atomic

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

ConcepTest PowerPoints

ConcepTest PowerPoints ConcepTest PowerPoints Chapter 30 Physics: Principles with Applications, 6 th edition Giancoli 2005 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for

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 38 and Chapter 39

Chapter 38 and Chapter 39 Chapter 38 and Chapter 39 State of 19th and very early 20th century physics: Light: 1. E&M Maxwell s equations > waves; J. J. Thompson s double slit experiment with light 2. Does light need a medium? >

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 22 Quantum Mechanics & Atomic Structure 22.1 Photon Theory of Light and The Photoelectric Effect Homework # 170

Chapter 22 Quantum Mechanics & Atomic Structure 22.1 Photon Theory of Light and The Photoelectric Effect Homework # 170 22.1 Photon Theory of Light and The Photoelectric Effect Homework # 170 See Homework #95 in "Chapter 12-Electrostatics" for the table of "Useful nformation" on atomic particles. 01. What is the energy

More information

Question 12.1: Choose the correct alternative from the clues given at the end of the each statement: (a) The size of the atom in Thomson s model is... the atomic size in Rutherford s model. (much greater

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

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

1. What is the minimum energy required to excite a mercury atom initially in the ground state? ev ev ev

1. What is the minimum energy required to excite a mercury atom initially in the ground state? ev ev ev Page 1 of 10 modern bank Name 25-MAY-05 1. What is the minimum energy required to excite a mercury atom initially in the ground state? 1. 4.64 ev 3. 10.20 ev 2. 5.74 ev 4. 10.38 ev 2. The diagram represents

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

Where are we? Check-In

Where are we? Check-In Where are we? Check-In ü Building Blocks of Matter ü Moles, molecules, grams, gases, ü The Bohr Model solutions, and percent composition Coulomb s Law ü Empirical and Molecular formulas Photoelectron Spectroscopy

More information

QUANTUM MECHANICS Chapter 12

QUANTUM MECHANICS Chapter 12 QUANTUM MECHANICS Chapter 12 Colours which appear through the Prism are to be derived from the Light of the white one Sir Issac Newton, 1704 Electromagnetic Radiation (prelude) FIG Electromagnetic Radiation

More information

Chapter 27. Early Quantum Theory and Models of the Atom

Chapter 27. Early Quantum Theory and Models of the Atom Ch-27-1 Chapter 27 Early Quantum Theory and Models of the Atom Questions 1. Does a lightbulb at a temperature of 2500 K produce as white a light as the Sun at 6000 K? Explain. 2. If energy is radiated

More information

CHAPTER 3 The Experimental Basis of Quantum Theory

CHAPTER 3 The Experimental Basis of Quantum Theory CHAPTER 3 The Experimental Basis of Quantum Theory 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 Discovery of the X Ray and the Electron Determination of Electron Charge Line Spectra Quantization As far as I can

More information

PHY293 Lecture #15. November 27, Quantum Mechanics and the Atom

PHY293 Lecture #15. November 27, Quantum Mechanics and the Atom PHY293 Lecture #15 November 27, 2017 1. Quantum Mechanics and the Atom The Thompson/Plum Pudding Model Thompson discovered the electron in 1894 (Nobel Prize in 1906) Heating materials (metals) causes corpuscles

More information

UNIT : QUANTUM THEORY AND THE ATOM

UNIT : QUANTUM THEORY AND THE ATOM Name St.No. Date(YY/MM/DD) / / Section UNIT 102-10: QUANTUM THEORY AND THE ATOM OBJECTIVES Atomic Spectra for Hydrogen, Mercury and Neon. 1. To observe various atomic spectra with a diffraction grating

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

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 Quantum Physics

Chapter 27 Quantum Physics Key Ideas Two Principles of Relativity: The laws of physics are the same for all uniformly moving observers. The speed of light is the same for all observers. Consequences: Different observers measure

More information

Atomic Structure Discovered. Dalton s Atomic Theory. Discovery of the Electron 10/30/2012

Atomic Structure Discovered. Dalton s Atomic Theory. Discovery of the Electron 10/30/2012 Atomic Structure Discovered Ancient Greeks Democritus (460-362 BC) - indivisible particles called atoms Prevailing argument (Plato and Aristotle) - matter is continuously and infinitely divisible John

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

1. Historical perspective

1. Historical perspective Atomic and Molecular Physics/Lecture notes presented by Dr. Fouad Attia Majeed/Third year students/college of Education (Ibn Hayyan)/Department of Physics/University of Babylon. 1. Historical perspective

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

CHAPTER 3 The Experimental Basis of Quantum

CHAPTER 3 The Experimental Basis of Quantum CHAPTER 3 The Experimental Basis of Quantum 3.1 Discovery of the X Ray and the Electron 3.2 Determination of Electron Charge 3.3 Line Spectra 3.4 Quantization 3.5 Blackbody Radiation 3.6 Photoelectric

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

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

Lecture 11 Atomic Structure

Lecture 11 Atomic Structure Lecture 11 Atomic Structure Earlier in the semester, you read about the discoveries that lead to the proposal of the nuclear atom, an atom of atomic number Z, composed of a positively charged nucleus surrounded

More information

Ch 7 Quantum Theory of the Atom (light and atomic structure)

Ch 7 Quantum Theory of the Atom (light and atomic structure) Ch 7 Quantum Theory of the Atom (light and atomic structure) Electromagnetic Radiation - Electromagnetic radiation consists of oscillations in electric and magnetic fields. The oscillations can be described

More information

Chapter 28. Atomic Physics

Chapter 28. Atomic Physics Chapter 28 Atomic Physics Quantum Numbers and Atomic Structure The characteristic wavelengths emitted by a hot gas can be understood using quantum numbers. No two electrons can have the same set of quantum

More information

RED. BLUE Light. Light-Matter

RED. BLUE Light.   Light-Matter 1 Light-Matter This experiment demonstrated that light behaves as a wave. Essentially Thomas Young passed a light of a single frequency ( colour) through a pair of closely spaced narrow slits and on the

More information

Physics 116. Nov 21, Session 31 De Broglie, duality, and uncertainty. R. J. Wilkes

Physics 116. Nov 21, Session 31 De Broglie, duality, and uncertainty. R. J. Wilkes Physics 116 Session 31 De Broglie, duality, and uncertainty Nov 21, 2011 R. J. Wilkes Email: ph116@u.washington.edu Announcements HW 6 due today Clicker scores have been updated on Webassign gradebook

More information

Physics 30 Modern Physics Unit: Atomic Basics

Physics 30 Modern Physics Unit: Atomic Basics Physics 30 Modern Physics Unit: Atomic Basics Models of the Atom The Greeks believed that if you kept dividing matter into smaller and smaller pieces, you would eventually come to a bit of matter that

More information

PHYS 3313 Section 001 Lecture #14

PHYS 3313 Section 001 Lecture #14 PHYS 3313 Section 001 Lecture #14 Monday, March 6, 2017 The Classic Atomic Model Bohr Radius Bohr s Hydrogen Model and Its Limitations Characteristic X-ray Spectra 1 Announcements Midterm Exam In class

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

Final Exam: Thursday 05/02 7:00 9:00 pm in STEW 183

Final Exam: Thursday 05/02 7:00 9:00 pm in STEW 183 Final Exam: Thursday 05/02 7:00 9:00 pm in STEW 183 Covers all readings, lectures, homework from Chapters 17 through 30 Be sure to bring your student ID card, calculator, pencil, and up to three onepage

More information

Physics 116. Nov 22, Session 32 Models of atoms. R. J. Wilkes

Physics 116. Nov 22, Session 32 Models of atoms. R. J. Wilkes Physics 116 Session 32 Models of atoms Nov 22, 2011 Thomson Rutherford R. J. Wilkes Email: ph116@u.washington.edu Announcements Exam 3 next week (Tuesday, 11/29) Usual format and procedures I ll post example

More information

Chapter 9: Electrons and the Periodic Table

Chapter 9: Electrons and the Periodic Table C h e m i s t r y 1 2 C h 9 : E l e c t r o n s a n d P e r i o d i c T a b l e P a g e 1 Chapter 9: Electrons and the Periodic Table Work on MasteringChemistry assignments What we have learned: Dalton

More information

Chapter 30 Quantum Physics 30.1 Blackbody Radiation and Planck s Hypothesis of Quantum Energy 30.2 Photons and the Photoelectric Effect 30.

Chapter 30 Quantum Physics 30.1 Blackbody Radiation and Planck s Hypothesis of Quantum Energy 30.2 Photons and the Photoelectric Effect 30. Chapter 30 Quantum Physics 30.1 Blackbody Radiation and Planck s Hypothesis of Quantum Energy 30.2 Photons and the Photoelectric Effect 30.3 The Mass and Momentum of a Photon 30.4 Photon Scattering and

More information

Chapter 7 Atomic Structure -1 Quantum Model of Atom. Dr. Sapna Gupta

Chapter 7 Atomic Structure -1 Quantum Model of Atom. Dr. Sapna Gupta Chapter 7 Atomic Structure -1 Quantum Model of Atom Dr. Sapna Gupta The Electromagnetic Spectrum The electromagnetic spectrum includes many different types of radiation which travel in waves. Visible light

More information

Bohr model and Franck-Hertz experiment

Bohr model and Franck-Hertz experiment Bohr model and Franck-Hertz experiment Announcements: Will finish up material in Chapter 5. There will be no class on Friday, Oct. 18. Will announce again! Still have a few midterms see me if you haven

More information

3. Particle nature of matter

3. Particle nature of matter 3. Particle nature of matter 3.1 atomic nature of matter Democrit(us) 470-380 B.C.: there is only atoms and empty space, everything else is mere opinion (atoms are indivisible) Dalton (chemist) 180: chemical

More information

Lecture PowerPoint. Chapter 32 Physics: Principles with Applications, 6 th edition Giancoli

Lecture PowerPoint. Chapter 32 Physics: Principles with Applications, 6 th edition Giancoli Lecture PowerPoint Chapter 32 Physics: Principles with Applications, 6 th edition Giancoli 2005 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for the

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

History of the Atomic Model

History of the Atomic Model Chapter 5 Lecture Chapter 5 Electronic Structure and Periodic Trends 5.1 Electromagnetic Radiation Learning Goal Compare the wavelength, frequency, and energy of electromagnetic radiation. Fifth Edition

More information

Physics 2D Lecture Slides Feb. 2, Sunil Sinha UCSD Physics

Physics 2D Lecture Slides Feb. 2, Sunil Sinha UCSD Physics Physics D Lecture Slides Feb., 010 Sunil Sinha UCSD Physics Thomson s Determination of e/m of the Electron In E Field alone, electron lands at D In B field alone, electron lands at E When E and B field

More information

I. Multiple Choice Questions (Type-I)

I. Multiple Choice Questions (Type-I) I. Multiple Choice Questions (Type-I) 1. Which of the following conclusions could not be derived from Rutherford s α -particle scattering experiement? (i) Most of the space in the atom is empty. (ii) The

More information

Lecture PowerPoints. Chapter 17 Physics: Principles with Applications, 6 th edition Giancoli

Lecture PowerPoints. Chapter 17 Physics: Principles with Applications, 6 th edition Giancoli Lecture PowerPoints Chapter 17 Physics: Principles with Applications, 6 th edition Giancoli 2005 Pearson Prentice Hall This work is protected by United States copyright laws and is provided solely for

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

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

Early Atomic Theories and the Origins of Quantum Theory. Chapter 3.1

Early Atomic Theories and the Origins of Quantum Theory. Chapter 3.1 Early Atomic Theories and the Origins of Quantum Theory Chapter 3.1 What is Matter Made of? People have wondered about the answer to this question for thousands of years Philosophers Matter is composed

More information

Explain how line spectra are produced. In your answer you should describe:

Explain how line spectra are produced. In your answer you should describe: The diagram below shows the line spectrum of a gas. Explain how line spectra are produced. In your answer you should describe: how the collisions of charged particles with gas atoms can cause the atoms

More information

The Hydrogen Atom According to Bohr

The Hydrogen Atom According to Bohr The Hydrogen Atom According to Bohr The atom We ve already talked about how tiny systems behave in strange ways. Now let s s talk about how a more complicated system behaves. The atom! Physics 9 4 Early

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

λ = h = h p mv λ = h mv FXA 2008 Candidates should be able to :

λ = h = h p mv λ = h mv FXA 2008 Candidates should be able to : 1 Candidates should be able to : Explain electron diffraction as evidence for the wave nature of particles like electrons. Explain that electrons travelling through polycrystalline graphite will be diffracted

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

SCH4U: History of the Quantum Theory

SCH4U: History of the Quantum Theory SCH4U: History of the Quantum Theory Black Body Radiation When an object is heated, it initially glows red hot and at higher temperatures becomes white hot. This white light must consist of all of the

More information

2.1- CLASSICAL CONCEPTS; Dr. A. DAYALAN, Former Prof & Head 1

2.1- CLASSICAL CONCEPTS; Dr. A. DAYALAN, Former Prof & Head 1 2.1- CLASSICAL CONCEPTS; Dr. A. DAYALAN, Former Prof & Head 1 QC-2 QUANTUM CHEMISTRY (Classical Concept) Dr. A. DAYALAN,Former Professor & Head, Dept. of Chemistry, LOYOLA COLLEGE (Autonomous), Chennai

More information

Lecture 32 April

Lecture 32 April Lecture 32 April 08. 2016. Hydrogen Discharge Tube and Emission of Discrete Wavelengths Description of the discrete Hydrogen Emission Spectrum by the Balmer (1884) Rydberg Ritz formula (1908) Cathode Ray

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