standard: 1i, 1j terms: p.117 article: 144 mastering concept: 146(30-38) practice prblems: 121(1-4), 124(5-6 lab write up: 125 home lab:954 #5 Homework cornell notes: 5.1 sec. assessment: 126 (7-11) mastering problems: 147(65-76)

New Terms Electromagnetic radiation Wavelength Frequency A form of energy that has wavelike behavior Wavelength The shortest distance between equivalent points on a wave Frequency The # of waves that pass through a given point per second

relationship Wavelength vs. frequency As wavelength increase, frequency decrease

Electromagnetic spectrum Quantum All forms of electromagnetic radiation Quantum The minimum amount of energy that can be gained or lost by an atom Planck’s constant Value used to determine the energy of a quantum

Photoelectric effect phenomenon where electrons are emitted from a metal’s surface when light of a certain frequency shines on the surface.

Sunlight takes about 8 minutes 17 seconds to travel the average distance from the surface of the Sun to the Earth. Exact values: 299,792,458 meters per second

Calculating wavelength of an EM wave Radio waves are used to transmit information on various channels. What is the wavelength of a radio wave having the frequency of 5.40 X 1010 Hz? V = 5.40 X 1010 Hz C = 3.00 X 108 m/s λ = ? m C = λV λ = C/V = 3.00 X 108 m/s 5.40 X 1010 1/s = 5.5 x 10-3 m 1/s or s-1 3.00 Exp or EE 8 ÷ 5.40 Exp or EE 10 =

Practice Problems: P. 121 (1-4) What is the frequency of green light, which has a wavelength of 4.9 x 10-7m? An X ray has wavelength of 1.15 x 10-10m. What is its frequency? What is the speed of an electromagnetic wave that has a frequency of 7.8 x 106 Hz? A popular radio station broadcasts with a frequency of 94.7 MHz. What is the wavelength of the broadcast? (1MHz = 106 Hz)

Calculating wavelength of an EM wave What is the frequency of green light, which has a wavelength of 4.9 x 10-7m? C = 3.00 X 108 m/s λ = 4.9 x 10-7m V = ? C = λV V = C/λ = 3.00 X 108 m/s 4.9 x 10-7m = 6.12 x 1014 1/s 3.00 Exp or EE 8 ÷ 4.90 Exp or EE -/+ 7 =

Calculating wavelength of an EM wave 2. An X ray has wavelength of 1.15 x 10-10m. What is its frequency? C = 3.00 X 108 m/s λ = 1.15 x 10-10m V = ? C = λV V = C/λ = 3.00 X 108 m/s 1.15 x 10-10m = 2.61 x 1018 1/s 3.00 Exp or EE 8 ÷ 1.15 Exp or EE -/+ 10 =

Your Turn... 3. What is the speed of an electromagnetic wave that has a frequency of 7.8 x 106 Hz? C = 3.00 X 108 m/s

Your Turn... 4. A popular radio station broadcasts with a frequency of 94.7 MHz. What is the wavelength of the broadcast? (1MHz = 106 Hz) C = 3.00 X 108 m/s V = 94.7 MHz (106 Hz = 1MHz )=9.47 x 107 s-1 λ = ? C = λV λ= C/V = 3.00 X 108 m/s 9.47 x 107 s-1 = 3.17 m 3.00 Exp or EE 8 ÷ 9.47 Exp or EE -/+ 7 =

Flame Test Lab 125

Gamma Radio

Visible EM Radiation The human eye can detect EM radiation within a 400 nm – 750 nm range. This radiation is processed and interpreted by our brains as color.

Element Color λ (nm) V =C/λ C=3x108 E = hv h=6.626x 10-34 λ (m) 1m=109nm V =C/λ C=3x108 E = hv h=6.626x 10-34 Barium Ba Yellow 590 Copper Cu Green/blue 520 Sodium Na orange 630 Calcium Ca Red/ Orange 620 6.2x10-7 4.8x1014 3.2x10-19

Element Color λ (nm) V =C/λ C=3x108 E = hv h=6.626x 10-34 λ (m) 1m=109nm V =C/λ C=3x108 E = hv h=6.626x 10-34 Lithium Red Sodium Yellow Potassium violet Calcium Red/ Orange 620 6.2x10-7 4.8x1014 3.2x10-19 Strontium Bright red

Practice Problems: 124(5-6) 5. What is the energy of each of the following types of radiation? 6.32 x 1020 s-1 9.50 x 1013 Hz 1.05 x 1016 s-1

Practice Problems: 124(5-6) 5. What is the energy of each of the following types of radiation? 6.32 x 1020 s-1 v = 6.32 x 1020 s-1 h = 6.626 X 10-34 J.s ? J Ephoton = hV Ephoton = 6.32 x 1020 s-1 (6.626 X 10-34 J.s) = 4.19 x 10-13 J 6.32 Exp or EE 20 x 6.626 Exp or EE -/+ 34=

Practice Problems: 124(5-6) 5. What is the energy of each of the following types of radiation? 9.50 x 1013 Hz v = 9.50 x 1013 s-1 h = 6.626 X 10-34 J.s ? J Ephoton = hV Ephoton = 9.50 x 1013 s-1 (6.626 X 10-34 J.s) = 6.29 x 10-20 J 1/s or s-1 9.50 Exp or EE 13x 6.626 Exp or EE -/+ 34=

Practice Problems: 124(5-6) 6. Use Figure 5-5 to determine the types of radiation described in problem 5 6.32 x 1020 s-1 b. 9.50 x 1013 Hz c. 1.05 x 1016 s-1