Post on 05-Jan-2016
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AnnouncementsTuesday, May 3
FINALWhen: Tuesday, May 10, 7:30 – 9:30 Where: in our usual room.
BRING YOUR 5” x 7” card with notes. BRING “problem” exams (misgraded, etc.)
HELP SESSIONS: JUST DROP IN FOR HELP!!!! Wednesday at 5 pm, here Next Monday at 7 pm, TBA
EXTRA CREDIT (10 PTS) Find the error in the hydrogen car article.
Today’s FactoidsPopulation of China: 1,300,000,000
(20% of global population)Population of USA: 300,000,000 Log10(China) = 9.1Log10(USA) = 8.5
U.S. –awarded Ph.D.’s in science & engineering: ~25,000/year
RedOx
Reduction OxidationLose oxygen Gain oxygen
Gain hydrogen Lose hydrogen
Gain electrons Lose electrons
A sample case2Na + 2H2O 2Na+ + H2 +
2OH-
Na was oxidized: Na Na+ + e- (electron lost)H was reduced: lost oxygenO no change: lost H but gained e-
Remember…we actually ran this reaction by dumping some sodium into water.
Another one
2 CH3OH 2 CH2O + H2
C: ???H: ???H: ???O: ???
Still another one (related to “butter vs. margarine”)
CH3CH2CH2CH=CHCH2CH3 + H2
CH3CH2CH2CH-CHCH2CH3 H H
C ?????H ?????
Secret Agents: all part of the semantics nightmare that is
RedOxSomething that promotes reduction: reducing agent
Example: K, Na, H, LiAlH4
Something that promotes oxidation: oxidizing agent
Example, O, F, Br, K2Cr2O7
Main Applications of RedOx
Recovery of metals from ores
Corrosion
Prevention of corrosion
Batteries
And the sons of Pullman porters & the sons of engineersRide their fathers' magic carpet made of steel
Mothers with their babes asleep, rockin' to the gentle beatAnd the rhythm of the rails is all they feel
City of New Orleans—Steve Goodman
Steel!
Images of steel production
Reducing Iron Ore to Make Steel:
from rust to riches
2 Fe2O3 + 3C 4 Fe + 3CO2
Rusti.e., ore
FromCoal
How steel is really made: http://www.sidmar.be/CONTENT/2c.htm
RedOx & Geography
COAL
IRON ORE
CARS
Electro-reduction for Aluminum
2Al2O3 4Al + 3O2
Electrons out
Electrons inPower Plant
Hydroelectric Power
Hydroelectric Power
Aircraft Industry
Why do we recycle aluminum?
Corrosion
2 Fe 2 Fe+2 + 4 e-
4e- + 2H2O + O2 4OH-
Electrons travel down nail
Batteries! What if we could trap those electrons, make
‘em do some work before the reduction step?
ENR vs XOM
Fuel Cells—Quick Intro
We are reliant on foreign oil. http://www.worldfuturefund.org/wffmaster/Charts-HTML/Energy/u
s-oil.htm
U.S. oilimports as a percentageof consumption
http://www.saudi-us-relations.org/newsletter/saudi-relations-12.html
Los Angeles Solar Parking Slots
At the other end of I-10
Hybrid VehiclesRedOx Chemistry Galore
“The car Detroit wants you to believe cannot be built.”But is that fair???
Hybrid Locomotive
Cool Fuel Cell Links
How Stuff Works Link: http://science.howstuffworks.com/fuel-cell1.htm
http://science.howstuffworks.com/framed.htm?parent=fuel-cell.htm&url=http://education.lanl.gov/resources/h2/gottesfeld/education.html
“Maybe I should invest in fuel cells.”
P. Russo, 1999
More Announcements
Pick up your HW4 papers!!
HW5 due 5 pm—no exceptions.HW5 answers by e-mail
Monday evening help session, 5 pmTuesday 7:30 am Final Exam (300 pts)Remember, only 5” x 7” cheat sheetNo-calculator bribe raised to 17% for final.