L04S08 LightWaves - Chem 1A L4"Light Waves Absorption...

Unformatted text preview: Chem 1A L4: "Light: Waves, Absorption, Emission" Weekly Review Sessions Thursday 5-7 p.m. 5105 Stanley Hall Amber Wise Drop-in Office Hours Mondays to Fridays 10-5 10See schedule posted at the door Location: 12B Latimer Hall A.Pines,M.Kubinec,UCB L4-1 Density of Gases CH3CH2CH2OH = molar density (all gases) = mass density (MW are equal) mass density = 0.0027 g/ml H O CH3CHCH3 2002 M. Kubinec L1-8 Combustion of Alcohols CH3CH2CH2OH + 9/2 O2 3 CO2 + 4 H2O MM Density (g/ml) gas liquid Reactions in Solution Concentration in Molar (M) 1 mole solute 1M = Liter solution What is [propanol] when 60 ml propanol] propanol is mixed with 40 ml H2O? A) > 1 M 2002 M. Kubinec Propanol CH3CH2CH2OH 60 Isopropanol Ethanol LD50 ~ 6g/kg 2002 M. Kubinec (g/mol) OH CH3CHCH3 0.003 0.80 0.003 0.78 0.002 0.94 L3-10 60 46 CH3CH2OH B) ~ 1 M C) < 1 M L4-2 L1-15 A.Pines,M.Kubinec,UCB Reactions in Solution What is [propanol] when 60 ml propanol] propanol is mixed with 40 ml H2O? 60 ml propanol ~ 60 x 0.8 g/ml = 48 g 60 g ~ 1 mole 48 g ~ 0.8 mole ~ 0.8 mole/0.1 L ~ 8 M A.Pines,M.Kubinec,UCB L4-3 A.Pines,M.Kubinec,UCB 1 Chem 1A L4: "Light: Waves, Absorption, Emission" ChemQuiz 3.4 What is the molar concentration of ethanol in a 90 proof whisky? A) ~ 2 M A.Pines,M.Kubinec,UCB B) ~ 5 M C) ~ 10 M L4-4 Light as a Wave Electromagnetic Radiation Diffraction and Interference :wavelength A A+B B Intensity ~ Probability Distribution Summary c c :speed = c :frequency = 400 nm = 700 nm A.Pines,M.Kubinec,UCB c= 3.0 x 108 m/s L6-4 A.Pines,M.Kubinec,UCB L6-6 Electromagnetic Spectrum 400 500 Visible -rays x-rays UV IR MW Radio, NMR, MRI Absorption and Continuous Emission 600 700 nm 10-16 10-12 10-8 A.Pines,M.Kubinec,UCB 10-4 100 104 108 m L6-5 A.Pines,M.Kubinec,UCB Line L6-10 Light as a Wave Electromagnetic Radiation c :wavelength :frequency c :speed =c = 400 nm = 700 nm A.Pines,M.Kubinec,UCB c = 3.0 x 108 m/s L4-7 A.Pines,M.Kubinec,UCB 2 Chem 1A L4: "Light: Waves, Absorption, Emission" Electromagnetic Spectrum 400 500 Visible -rays x-rays UV IR MW Radio,NMR,MRI 600 700 nm 10-16 10-12 10-8 10-4 100 104 108 m L4-8 A.Pines,M.Kubinec,UCB Diffraction and Interference Intensity ~ Probability Distribution A A.Pines,M.Kubinec,UCB L4-9 Diffraction and Interference Intensity ~ B Probability Distribution A.Pines,M.Kubinec,UCB L4-10 A.Pines,M.Kubinec,UCB 3 Chem 1A L4: "Light: Waves, Absorption, Emission" Diffraction and Interference Intensity ~ A B Probability Distribution A.Pines,M.Kubinec,UCB L4-11 Diffraction and Interference Intensity A + B ~ Probability Distribution A.Pines,M.Kubinec,UCB L4-12 Constructive and destructive interference of waves A.Pines,M.Kubinec,UCB L4-13 A.Pines,M.Kubinec,UCB 4 Chem 1A L4: "Light: Waves, Absorption, Emission" Diffraction and Interference Intensity A + B ~ Probability Distribution A.Pines,M.Kubinec,UCB L4-14 ChemQuiz 4.1 How will the two-slit twointerference pattern change upon increase of ? A) A.Pines,M.Kubinec,UCB B) C) L4-15 ChemQuiz 4.1 Solution Travels farther Larger = Greater spacing Equal path lengths A) A.Pines,M.Kubinec,UCB B) C) L4-16 A.Pines,M.Kubinec,UCB 5 Chem 1A L4: "Light: Waves, Absorption, Emission" Absorption and Continuous Emission Line A.Pines,M.Kubinec,UCB L4-17 ChemQuiz 4.2 What color is an object with the absorption spectrum shown? A) ~ blue A.Pines,M.Kubinec,UCB B) ~ green C) ~ red L4-18 3--DImage 3 D Image A.Pines,M.Kubinec,UCB L4-20 A.Pines,M.Kubinec,UCB 6 Chem 1A L4: "Light: Waves, Absorption, Emission" 3-D Image A.Pines,M.Kubinec,UCB L4-21 3-D Image A.Pines,M.Kubinec,UCB L4-22 ChemQuiz 4.3 Glass is transparent. transparent. Which one is its absorption spectrum ? A) I A.Pines,M.Kubinec,UCB Absorption I II III UV VIS IR B) II C) III L4-23 A.Pines,M.Kubinec,UCB 7 Chem 1A L4: "Light: Waves, Absorption, Emission" Lecture Complete A.Pines,M.Kubinec,UCB L4-25 A.Pines,M.Kubinec,UCB 8 ...
View Full Document