1. Take out your Homework on Electron Configuration and Orbital Diagrams
Science Starter
How man electrons does neutral Chlorine have?
What letter block is Chlorine in? (s,p,d,f)
What group is Chlorine in?
How many valence electrons does Chlroine have?
What element has the electron configuration below?
1s22s22p63s23p5

2. Today’s Agenda Science Starter
Flame Test Demo  How Fireworks are made!
Bohr Model of Hydrogen
Periodic Trends Packet
Exit Ticket

4. FLAME TEST DEMO:

5. Electromagnetic Spectrum

6. Unit 2: The Electron The Bohr Model of Hydrogen

7. Electromagnetic Radiation
Light consists of electromagnetic waves.
EX: radio waves, X-rays, UV rays, infrared rays, etc.
When light passes through a prism, different frequencies separate in a spectrum of colors (i.e. rainbow)

10. Atomic Spectra
Ground state: lowest possible energy of an electron (n=1)
Electrons move to another energy level when energy is added
Energy is released as light when an electron drops an energy level.

12. Quantum Mechanics
Quantum mechanics- describes motions of subatomic particles and atoms as waves.
Einstein-proposed that light existed as a particle, as well as a wave.
Photon- bundles of light energy
Heisenberg Uncertainty Principle- it is impossible to know exactly both the velocity and position of an electron at the same time.

13. Consensus
When energy is supplied to an atom the electrons move to an excited state
When they return to their “ground state” they emit energy by radiating light
Different colors of light are emitted based on the energy levels that the electron falls from

14. BOHR’S MODEL
First, lets look at the two separate graphics that represent this model.
DO NOT LOSE THIS SHEET

15. Higher (n) = more excited ‘state’ or energy level!
Jump from higher (excited state) to a lower energy level.
THIS ACTION GIVES OFF LIGHT!!!

17. Practice 1
1) When an electron becomes excited and moves to a higher energy level, is light emitted?

18. Practice 2
2) When an electron moves from the excited to the ground state, is light emitted?

19. Practice 3
3) If an electron in a hydrogen atom moves from n=5 to n=2, what color of light is emitted?

22. Practice 4
4) If an electron in a hydrogen atom moves from n=4 to n=1, what type of light is emitted?

25. Practice 5
5) If an electron in a hydrogen atom moves from n=5 to n=3, what type of light is emitted?

28. Practice 6
6) If an electron in a hydrogen atom moves from n=1 to n=3, is light emitted? If so, what kind?

29. Practice 7
7) If you have light with a wavelength of 600nm what color is the light?

31. Practice 8
8) If you have light with a wavelength of 475nm what color is the light?

33. Practice 9
9) In order to emit red light, what energy level transition must occur?

36. Practice 10
10) In order to emit violet light, what energy level transition must occur?

39. Exit Ticket

40. Exit Ticket What element is in group 2 period 3? (2.1)
What is a valence electron? (2.1)
Write the electron configuration (both standard AND noble gas) and the orbital diagram for Iron (X=26). (2.2)
In order to emit BLUE light, what energy level transition must occur? (2.3)