1. Modern Chemistry Chapter 4 Arrangement of Electrons in Atoms
Sections 1-3
The Development of a New Atomic Model
The Quantum Model of the Atom
Electron Configurations

2. The Development of a New Atomic Model
Section 1
The Development of a New Atomic Model
Chapter 4 Section 1 New Atomic Model pages

3. Chapter 4 Section 1 New Atomic Model pages 97-103
Electromagnetic radiation
Electromagnetic spectrum
Wavelength
Frequency
Photoelectric effect
Quantum
Photon
Ground State
Excited state
Line-emission spectrum
Continuous spectrum
Section 1 Vocabulary
Chapter 4 Section 1 New Atomic Model pages

4. Chapter 4 Section 1 New Atomic Model pages 97-103
Properties of Light
Electromagnetic Radiation: a form of energy that exhibits wavelike behavior as it travels through space.
Wavelength: the distance between corresponding points on adjacent waves
Frequency: the number of waves that pass a given point in a specific time.
Chapter 4 Section 1 New Atomic Model pages

5. Wavelength and Frequency Image
p. 98
Chapter 4 Section 1 New Atomic Model pages

6. Electromagnetic Spectrum Image
Chapter 4 Section 1 New Atomic Model pages

7. Electromagnetic Spectrum Image
Chapter 4 Section 1 New Atomic Model pages

8. Chapter 4 Section 1 New Atomic Model pages 97-103
Properties of Light
wavelength x frequency = speed of light
 x  = c
Visible Light = R O Y G B I V
Long  Low  Low E
Short  High  High E
Chapter 4 Section 1 New Atomic Model pages

9. The Photoelectric Effect
Max Planck proposed that energy is proportional to the frequency of the electromagnetic wave.
Electromagnetic energy is emitted from objects in small packages called quanta.
E = h 
Planck’s constant
h = x J•sec
Chapter 4 Section 1 New Atomic Model pages

10. Quanitization of Energy Animation
Chapter 4 Section 1 New Atomic Model pages

11. The Photoelectric Effect
Albert Einstein expanded on Planck’s idea.
Electromagnetic radiation has a dual wave-particle nature.
A particle of light is a photon.
Photon: a particle of electromagnetic radiation having zero mass and carrying a quantum of energy.
Ephoton = h 
Chapter 4 Section 1 New Atomic Model pages

12. Energy of a Photon Animation
Chapter 4 Section 1 New Atomic Model pages

13. The Photoelectric Effect
The photoelectric effect refers to the emission of electrons from a metal when light shines on the metal.
p. 99
Chapter 4 Section 1 New Atomic Model pages

14. Photoelectric Effect Animaiton
Chapter 4 Section 1 New Atomic Model pages

15. The Photoelectric Effect
To knock an electron loose,
it must be hit with a photon which
possesses a minimum amount of energy.
This energy corresponds to its frequency.
Different metals hold electrons more or less tightly
So different metals require different frequencies to show the photoelectric effect.
Chapter 4 Section 1 New Atomic Model pages

16. The H-Atom’s Line Emission Spectrum
Electric current is passed through a vacuum tube with hydrogen in it.
A glow is produced
When shined through a prism a line emission spectrum is produced
p. 101
Chapter 4 Section 1 New Atomic Model pages

17. Hydrogen’s Line Emission Spectrum
Insert Glencoe Disk 1
Chapter 4 Section 1 New Atomic Model pages

18. Absorption and Emission Spectrum Animation
Chapter 4 Section 1 New Atomic Model pages

19. Line Emission Spectrum
Insert Glencoe Disk 1
Chapter 4 Section 1 New Atomic Model pages

20. Chapter 4 Section 1 New Atomic Model pages 97-103
Bohr Model of the Atom
Niels Bohr proposed orbits for the electrons
Each orbit has a fixed energy
Lower energy orbits are closer to the nucleus
Between orbits the electron cannot exist
Chapter 4 Section 1 New Atomic Model pages

21. Explaining the Line Emission Spectrum
An electron absorbs a specific amount of energy (absorption) and moves from its ground state to an excited state
Chapter 4 Section 1 New Atomic Model pages

22. Explaining the Line Emission Spectrum
The electron returns to its ground state and emits a photon (emission).
Chapter 4 Section 1 New Atomic Model pages

23. Explaining the Line Emission Spectrum
This photon has an energy corresponding to the difference between the two states.
This photon has a specific E, ,  and color.
Chapter 4 Section 1 New Atomic Model pages

24. Photon Emission and Absorption Image
Chapter 4 Section 1 New Atomic Model pages

25. Chapter 4 Section 1 New Atomic Model pages 97-103
Bohr Model of the Atom
Bohr’s calculated values for the lines agreed with the values observed for the lines in each series.
However, it did not explain the spectra of atoms with more than one electron.
Chapter 4 Section 1 New Atomic Model pages

26. Bohr Model of the Atom Animation
Chapter 4 Section 1 New Atomic Model pages

27. Chapter 4 Section 1 New Atomic Model pages 97-103
Bohr and Einstein
Chapter 4 Section 1 New Atomic Model pages

28. Chapter 4 Section 1 New Atomic Model pages 97-103
Section 1 Homework
Chapter 4 Section 1 New Atomic Model pages