 1 Homework Assignment 1: General Chemistry Review (due 2/12/2008)
 2 Homework Assignment 2: Room Energy Audit (due 2/19/2008)
 3 Homework Assignment 3: The Hybrid Car (due 2/21/2008)
 4 Homework Assignment 4: Book Problems (due 2/28/2008)
 5 Homework Assignment 5: Due 3/11/2008
 6 Homework Assignment 6: Due 3/20/2008
 7 Extra Credit: Due4/3/2008 (Max 5 points on Exam 1)
 8 Homework Assignment 7: Due 4/8/2008
Homework Assignment 1: General Chemistry Review (due 2/12/2008)
 Get a General Chemistry text that you may use as a reference for the semester.
 Complete the attached CH141 and CH142 exams (you may consult each other, but must submit your own work). Please turn in a hard copy in class.
Ch142 Final 2000.pdf CH141 Final Exam 2003.pdf
Homework Assignment 2: Room Energy Audit (due 2/19/2008)
Every student will help prepare a Colby student energy audit of electrical appliances used by the student body. Start by claiming an appliance by adding your name to the table below. You may fill in the rest of your row at a later date.
Name 
Appliance 
Energy Consumption (J/year) 
Number on Campus 
Total Energy 

Sharon Fuller 
microwave 
3.73 * 10^4 kJ/year 
1077.1 
4.01 * 10^7 kJ 
Katie Billington 
Printer 



Mengfei Zhang 
desk lamp 
6.350*10^8 J/year 
1475 
9.366*10^8 KJ 
Sasha Bartels 
mini fridge 
6.16*10^16 J/year 
933 
2.9*10^9 kJ/year 
Brittany Tschaen 
Television 
7.45 *10^7 J /yr 
533.4 
3.97*10^7 kJ/year 
Dan Heinrich 
Stereo/Speakers 
1.2 * 10^9 J/yr 
871 
1.04 * 10^9 kJ/yr 
Li Yu Chan 
cell phone & charger 
13.6 * 10^3 kJ 
1555.8 
2.12 * 10^7 kJ 
Brian DiMento 
Christmas lights 
1.69 * 10^8 J/year 
568 
9.60 * 10^7 kJ/yr 
Rob Dillon 
PS2 
Running: 6.54 * 10^4 kJ/year 
373 
3.86 * 10^7 kJ/year 
Mischa Noll 
iPod 
2.07*10^6 J/year 
1623 
3.36*10^6 kJ/year 
Katie Harris 
Blow Dryer 
3.97E5 kJ 
1023.1 
4.06*10^8 kJ/yr 
Kristina Shiroka 
Fan 



Elissa Teasdale 
Computer/Laptop 
9.3*10^5 kJ/year 
1875 
1.74*10^9 kJ/year 
Julia Coffin 
Alarm clock 
3.28*10^8 J/year 
778 
2.55*10^8 kJ/year 
Lane Mahoney 
DVD player 
8.9 * 10^3 kJ/year 
1120.2 
9.97 * 10^6 kJ/year 
Cat Zweig 
Coffee Maker 



Jason Hine 
Hair Straightener 
5.796 x 10^6 J/year 
560.1 
3.246 x 10^6 kJ/year 
Brynna Patel 
N64 
3.0*10^4 kJ/year 
60 
1.8*10^6 kJ/year 


















total 
6.5 x 10^9 kJ/yr 
Once you have selected the appliance, survey 10 or more rooms to get a statistical sampling of the appliance frequency on campus. Determine the energy consumed by the appliance over the course of the academic year and compute the total energy consumed by all students using the appliance. Put your data in the table above and provide the details on your appliance and your calculations below. This assignment is only submitted on this page.
Post answers to assignment 1 below: (list name, appliance, and then details)
Steve Jobs, Apple laptop computer
Details on the calculations for computer energy consumption ....
_______________________________________________________________________________________________
Li Yu Chan, Cell phone charger
Sample 
Brand 
Voltage (V) 
Amperes (A) 
1 
Motorola 
5.00 
0.85 
2 
Sony Ericsson 
4.90 
0.45 
3 
Black Berry 
5.00 
0.75 
4 
Nokia 
5.70 
0.80 
5 
Motorola 
5.10 
0.80 
6 
Nokia 
5.30 
0.50 
7 
Unbranded 
5.00 
0.60 
8 
Sony Ericsson 
4.90 
0.45 
9 
Samsung 
5.00 
0.70 
10 
Motorola 
5.00 
0.85 
Average 
 
5.09 
0.68 
Average Power = 5.09 * 0.68 = 3.46 W
[DWK: Watch your order of operations in the average power calculation.
The average power is not the same as the average voltage x average amps. However in this case it will be close]
Average energy consumption per year, assuming 3 hours daily use = 3.46 J/sec *60 sec/min * 60 min/hr * 3 hr/ day * 365 days = 13.6 *10^3 kJ
Total Energy based on probability that 10/12 students have cell phone chargers = (13.6*10^6) * 10/12* 1867 = 2.12*10^7 kJ
__Katie Harris, Blow Dryer

Brand 
Voltage (V) 
Current (A) 
Power (W) 
1 
Jilbere 
125 
10 
1250 
2 
Physique 
125 
15 
1875 
3 
Revlon 
125 
15 
1875 
4 
Conair 
125 
15 
1875 
5 
Perfection Classic 
125 
15 
1875 
6 
Vidal Sassoon 
125 
15 
1875 
7 
Conair 
125 
15 
1875 
8 
Conair 
125 
15 
1875 
9 
Conair 
125 
15 
1875 
10 
Conair 
125 
15 
1875 
Average 



1812.5 
Average Energy Consuption a year assuming 10 minutes daily use.
1812.5 J/sec * 60 sec/min * 10 min/day * 365 day/year = 3.97E8 J
Assuming every female (54.8%) on campus and no males use a blow dryer (some guys have hair driers)
3.97E8 J * 1867 * 54.8% = 4.06E11 J = 4.06E8 kJ
___________________________________________________________________________
Sharon Fuller, microwave
120V * 7.5A = 900W
Average energy consumption per year assuming 3 minutes daily use:
900 J/sec * 60 sec/min * 3 min/day * 230 day/year = 3.73 * 10^7 J = 3.73 * 10^4 kJ
With 15 microwaves per 26 students in survey:
3.73 x 10^4 kJ * 1867 students * (15/26) = 4.01 * 10^7 kJ
_____________________________________________________________________________
Brian DiMento, Christmas Lights
120V * 0.34A = 40.8W
Energy consumption assuming 5 hours of daily use, over an academic year (approximately 230 days on campus):
40.8 J/sec * 60 sec/min * 60 min/hr * 5 hr/day * 230 day/year = 1.69 * 10^8 J/year
Survey: 7 100 bulb strands found per 23 students.
1.69 * 10^8 J * 1867 students * (7/23) = 9.60 * 10^10 J total
Mengfei Zhang, Desk Lamp
sample number 
Power 
Time of use per year 
Energy consumed per year 

1 
20w 
52hr * 3600s/hr=187200s 
3.744*10^6 J 
2 
20w 
2184hr * 3600s/hr=7862400s 
1.572*10^8 J 
3 
60w 
104hr * 3600s/hr=374400s 
2.246*10^7 J 
4 
40w 
1092hr * 3600s/hr=3931200s 
1.572*10^8 J 
5 
60w 
104hr * 3600s/hr=374400s 
2.246*10^7 J 
6 
60w 
520hr * 3600s/hr=1872000s 
3.744*10^7 J 
7 
60w 
52hr *3600s/hr=187200s 
1.123*10^7 J 
8. 
75w 
208hr * 3600s/hr=748800s 
5.616*10^7 J 
9. 
13w 
208hr * 3600s/hr=748800s 
9.734*10^6 J 
10. 
60w 
676hr * 3600s/hr=2433600s 
1.460*10^8 J 
11. 
60w 
520hr * 3600s/hr=187200s 
1.123*10^7 J 




Average energy consumed per year by one desk lamp:
(3.744*10^6+1.572*10^8+2.246*10^7+1.572*10^8+2.246*10^7+3.744*10^7
+1.123*10^7+5.616*10^7+9.734*10^6+1.460*10^8+1.123*10^7)J /11 =6.350*10^8J=6.350*10^5 KJ
In the survey, 79% students use lamps, and each uses one. Number of students on campus is 1867. Number of desk lamps on campus : 79%*1*1867=1475
Total energy consumed: 6.350*10^5 KJ * 1475= 9.366*10^8 KJ
Julia Coffin, Alarm clock
15V*1.1A=16.5W
Energy consumption is assuming the alarm clock remains plugged in, over an academic year (approximately 230 days on campus)
Energy Consumption: 16.5 J/sec * 60 sec/min * 60 min/hr * 24 hr/day * 230 day/year = 3.28*10^8 J/year
In the survey: Number of students on campus is 1867. Number of alarm clocks on campus : (41.67%/100)*1867=778 alarm clocks
Survey: 5 alarm clocks found per 12 students sampled.
Total Energy Consumption: (3.28*10^8) J/year * 1867 students * (5/12) = 2.55*10^11 J/year total
Sasha Bartels, minifridge
120V*1.3A=156W
fridge remains plugged in constantly for the 230 days on campus
Energy Consumption: 156 J/sec * 60 sec/min * 60 min/ hr * 24 hrs/day * 230 days/year = 3.1*10^9 J/year
In survey, found about 1 minifridge per 2 people. 1867 students/2=933 minifridges on campus
Total Energy Consumption on campus: 3.1*10^9 J/year * 933 minifridges= 2.9*10^12 J/year
Dan Heinrich, stereo/speakers
Average speaker wattage surveyed from 15 students, 60 W.
7/15 students had speakers, .47 * 1867 students = 871 stereos
Averaging 30 min of daily use for 230 days on campus a year.
Energy Consumption: 60 J/s * 60 s/min * 60 min/hr *24 hrs/day * 230 days/yr = 1.2 * 10^9 J/yr per stereo
Total Energy Consumption at Colby for stereo use: 1.2 * 10^9 J/yr * 871 stereos = 1.04 * 10^12 J/yr = 1.04 * 10^9 kJ/yr

Mischa Noll, iPod
iPod wattage: 5.0 V * 1.0 A = 5.0 W
20/23 surveyed students had ipods, therefore this translates to 86.95% or 1623 Colby students.
If used 30 minutes a day on average, (5 J/s)(60 s/min)(30 minutes)=9,000 J/person/day
Since 230 days are spent on campus each academic year, (*230) there are 2.07*10^6 J/person/year
Multiply this by the 1623 students and we get 3.36*10^9 J/year or 3.36*10^6 kJ per year used at Colby
Elissa Teasdale, Laptop
Sample 
Voltage (V) 
Amperes (A) 
Power (W) 
1 
19.5 
4.62 
90.09 
2 
18.5 
4.6 
85.1 
3 
18.5 
4.6 
85.1 
4 
19.5 
4.62 
90.09 
5 
16.5 
3.65 
60.225 
6 
15 
5 
75 
7 
14.8 
6.6 
97.68 
8 
14.8 
6.6 
97.68 
9 
18.5 
4.6 
85.1 
10 
24 
1.875 
45 
Average 


81.10 
100% of the students surveyed owned and used their laptops. The energy consumption calculation is based off of the average hours the laptop was plugged in per day (13.9 hours) by the students surveyed for throughout the academic year (approximately 230 days). The number of students on campus = 1867.
Energy Consumption: (81.1 J/sec)(60 sec/min)(60 min/hr)(13.9 hr/day)(230 days/1 academic year) = 9.3*10^8 J/year = 9.3*10^5 kJ/year
Total Energy Consumption of laptops by students on campus: (9.3*10^8 J/year)(10/10)(1867 students) = 1.74*10^12 J/year = 1.74*10^9 kJ/year
Brynna Patel, Nintendo 64
30 people asked 3 machines
Multiple people only need one machine about 60 on campus
Average time played per day: 1.375 hours
Machine uses 26 watts so.....
Energy Consumption: (26 J/sec)(60 sec/min)(60 min/hr)(1.375 hr/day)(230 days/1 academic year) = 3.0*10^7 J/year or 3.0*10^4 kJ/academic year
Total Energy Consumption (during one academic year at Colby): (3.0*10^4 kJ/year)(60 machines on campus) = 1.8*10^6 kJ/academic year
Rob Dillon, PS2

W 
kJ/hr 
avg hrs used/day 
avg hrs used/academic year 
kJ/year 

Running 
79 
284.4 
1 
230 
6.54*10^4 
Standby 
2 
7.2 
23 
5290 
3.81*10^4 
Energy Consumption:
Running: (79 J/sec)(1 kJ/1000 J)(60 sec/min)((60 min/hr)(1 hr/day)(230 days/1 academic year) = 6.54 * 10^4 kJ/ year
Standby: (2 J/sec)(1 kJ/1000 J)(60 sec/min)((60 min/hr)(23 hr/day)(230 days/1 academic year) = 3.81 * 10^4 kJ/ year
While running the PS2 uses 79W and while its on standby it uses 2W. 20% of the students surveyed owned a PS2. The total # of students is 1867. Total students with PS2 is 373.
Total Energy consumption of PS2 by students:
Running: (6.54*10^4 kJ/ year)(373 students) = 2.44*10^7 kJ/year
Standby: (3.81*10^4 kJ/year)(373 students) = 1.42*10^7 kJ/year Total: 2.44 + 1.42 = 3.86 * 10^7 kJ/year
Brittany Tschaen, Television
120V * .75A = 90W
Average energy consumption per year assuming 1 hour daily use:
90 J/sec * 60 sec/min * 60 min/hr * 1 hr/day * 230 day/year = 7.45 *10^7 J/year = 7.45 * 10^4 kJ/year
Survey Results: 6 microwaves per 21 students
7.45 * 10^4 kJ/year * 1867 students * (6/21) = 3.97 * 10^7 kJ/year
Lane Mahoney, DVD player
DVD player wattage: 15 W
Energy Consumption per year assuming 5 hours weekly use and 33 weeks at Colby:
(15 J/sec) (60 sec/min) (60 min/hr) (5 hr/week) (33 weeks/year) = 8.9 x 10^6 J/year = 8.9 x 10^3 kJ/year
Number on Campus: Surveyed 10 rooms, 5 singles and 5 doubles: found that for every 15 students there are 9 DVD players
(3/5) (1867 students) = 1120.2 DVD players on campus
Total Energy Consumption per year at Colby:
(8.9 x 10^3 kJ/year) (1120.2 DVD players) = 9.97 x 10^6 kJ/year
Jason Hine, Hair Straightener
Sample 
watts 

1 
150 
2 
120 
3 
100 
4 
150 
5 
95 
6 
85 
average wattage = 116.67 W
average usage = 3.6 min/day
33 weeks a year at Colby
116.67 J/s * 60 sec/min * 3.6 min/day * 230 days/year = 5.796 x 10^6 J/year
6 straighteners per 20 students, 1867 students at Colby
5.796 x 10^6 J/year * 1867 students * (6/20) = 3.246 x 10^9 J/year
Homework Assignment 3: The Hybrid Car (due 2/21/2008)
Using the US DOE Hybrid vehicle cost calculator, compare the lifetime cost of running a hybrid vehicle versus a conventional vehicle of the same size. Each group of four students should select a different vehicle size class. Use current fuel prices, a 10 year vehicle lifetime, and an annual millage of 15,000 miles. The hybrid vehicles will save gasoline and, therefore, reduce carbon dioxide emissions. How much would it cost to purchase carbon credits to offset the increased gasoline consumption of a conventional powered car? How would purchasing carbon credits change the economics of running a hybrid versus a conventional car? Please show your work and provide details on your calculations.
Group Assignments for this assignment:
Group I
Hine, Jason F.
Chan, Li Yu
DiMento, Brian P.
Shiroka, Kristina A.
Group II
Zhang, Mengfei
Noll, Michael S.
Bradley, Sharonda Q.
Fuller, Sharon R.
Group III
Dillon, Robert W.
Billington, Kaitlyn E.
Bartels, Sarah E.
Patel, Brynna M.
Group IV
Teasdale, Elissa L.
Zweig, Catherine E.
Melese, Mesay
Harris, Katie
Group V
Tschaen, Brittany A.
Mahoney, Lane J.
Heinrich, Daniel G.
Coffin, Julia P.
Post answers to assignment 2 below: (list names of group members at the beginning of each question).
Your answer should be in narrative form with links to external data sources and specifics on any calculations. Each student in the group should contribute to the answer. This assignment is only submitted on this page.
[Tschaen, Brittany A., Mahoney, Lane J., Heinrich, Daniel G., Coffin, Julia P.]
Vehicle Class: Midsize Sedan
Car data taken from the DOE Hybrid Vehicle Cost Calculator:
Hybrid Vehicle: Lexus GS 430h = cumulative cost $61,920
Conventional Vehicle: Lexus GS 450 = cumulative cost $52,088
Hybrid lifetime emissions savings from carbon dioxide= 29,880 lbs
Cost of Carbon Credits = $75.00 from www.carbonfund.org for 30,000 lbs.
Final Hybrid Vehicle Cost: $61,920.
Final Conventional Vehicle Cost: $52,088 + $75.00 = $52,163.
As of now, it is still more economical to purchase a conventional vehicle and carbon credits than to purchase a hybrid vehicle. In fact, one would save $9,757 if they were to purchase carbon credits and a conventional vehicle (6192052163) and be equally green.
Dillon, Rob / Bartel, Sasha / Patel, Brynna
Vehicle Class: SUV
Hybrid Vehicle: Ford Escape (hybrid model) / cumulative cost = $37,525.44
Conventional Vehicle: Ford Escape / cumulative cost = $36,745.12
Hybrid Lifetime emissions savings from CO2 = 24,624 lbs.
Cost of Carbon Credits = 30,000lbs Carbon Offset  $148.50 from www.terrapass.com
Final Hybrid Cost: $37,525.44
Final Conventional Cost: $36,745.12 + $148.50 = $36,893.62
It is still more economical to buy the conventional vehicle and carbon credits based on our comparison. You would save a little under $1,000 over the hybrid.
Teasdale, Elissa & Harris, Katie
Vehicle Class: Small Car
Hybrid Vehicle: Toyota Camry cumulative cost =$34,755.36
Conventional Vehicle: Toyota Camry cumulative cost=$32,673.34
Hybrid Lifetime emissions savings from carbon dioxide = 31,239lbs.
Cost of carbon credits = $5.50/ton (http://www.carbonfund.org/) 31,239/2000 * 5.50 = $85.91
Final Hybrid Cost =$ 34,755.36
Final Conventional Cost = $ 32,673.34 + $85.91 = $ 32,759.25
Fuel Price $3.02 (http://tonto.eia.doe.gov/oog/info/gdu/gasdiesel.asp)
Economically it makes sense to buy a conventional Toyota Camry. It's as equally good for the environment to buy equal carbon credits that you would save from the lifetime emissions from a hybrid. In fact you save about $2000.
Brian DiMento, Li Yu Chan, Jason Hine
Vehicle Class: Pickup Truck
Car data taken from the DOE Hybrid Vehicle Cost Calculator:
Hybrid Vehicle: Chevrolet Silverado 1500HD Cls = cumulative cost $52,086.27
Conventional Vehicle: Chevrolet Silverado 1500 = cumulative cost $50,006.27
Hybrid lifetime emissions savings from carbon dioxide= 19,866 lbs.
Cost of Carbon Credits = $99.00 for 20,000 lbs carbon offset (www.terrapass.com)
Final Conventional Vehicle Cost: $50,006.27
Final Hybrid Vehicle Cost: $52,086.27 + $99.00 = $52185.27
Fuel Price: $3.04 (http://www.eia.doe.gov/oil_gas/petroleum/data_publications/wrgp/mogas_home_page.html)
City Driving: 50% of the time
It is more economical to purchase a conventional truck than a hybrid. Over its 10 year lifetime, it would cost $2179.00 more to own the hybrid truck (after buying carbon credits). The hybrid truck actually produced more carbon than the conventional truck, potentially because of its larger engine that resulted in a lower mpg. Because of this, the hybrid truck owner would be the one buying the credits. There were no exactly comparable trucks in this class to test to avoid this conclusion.
Fuller, Sharon; Zhang, Mengfei; Noll, Mischa
Vehicle Class:Sedan Driven 25,000 miles per year
Fuel Cost: $3.05/gallon
Hybrid Vehicle: Toyota Camry Hybrid cumulative cost =$45,449.96
Conventional Vehicle: Toyota Camry cumulative cost=$45,779.05
Hybrid Lifetime emissions savings from carbon dioxide = 52,064 lbs.
Cost of carbon credits = $5.50 per ton (www.carbonfund.org) * 52,064 lbs/2000 = $143.18
Final Hybrid Cost =$45,449.96
Final Conventional Cost = $45,779.05 + $143.18 =$45,922.23
Even before purchasing carbon credits, it is cheaper to get the hybrid camry. By driving the car longer distances, it becomes worth it to invest the extra couple of thousand dollars in the beginning.
Homework Assignment 4: Book Problems (due 2/28/2008)
Please hand in your solutions to book problems: Problem set I: 1, 2, 6, 8, 9, 12, 19, 22, 23, 24, 25
Answers to problems:
1d 5.57x10^9 kJ
2 10^16 tons
6 57% as efficient
8 about the same
9 coal mass flow 766 kg CO2, 11.6 kg SO2
12 1.4x10^16 inonizations/yr
19c $15825
22
23 6 times the volume
24c 175 percent
25 68%
Homework Assignment 5: Due 3/11/2008
Book Problems: page 242: 2, 4, 8, 10, 20, 21, calculate the pressure and mixing ratio of oxygen and nitrogen in the atmosphere at 2,000, 4,000, and 10,000 meters altitude. Book questions, pressure calculation
Prepare two questions to ask our speaker on 3/11. Be prepared to ask your question, if appropriate, at the end of Prof. Rowland's talk. We will follow the Department of Chemistry three question rule  the first three questions of a seminar must be from students. You will turn your questions with your homework at the end of class.
Homework Assignment 6: Due 3/20/2008
A significant source of CFCs to the atmosphere is through their use as refrigerants in air conditioning systems and subsequent leakage to the atmosphere. Colby is making an effort to reduce the emission of CFC (or HCFCs) by designing new building to LEED specifications that require carefully designed air conditioning systems. LEED is a building standard used by the US Green Building Council to reduce the environmental impact of construction. For the purposes of this homework assignment, lets assume Colby is renovating Treworgy next year and want to install air conditioning. Treworgy has about 5000 ft^2 of space and would require (love the units) 10 tons of compressor capacity to meet the cooling requirement of the building. Assuming a 10 ton AC unit will contain 70 lbs of refrigerant, is it possible to make the AC installation LEED certified? After reading the attached links use the CFC calculator from Trane to calculate the LEED credit (or not) for the air conditioning unit you choose. What are the tradeoffs between different refrigerant types?
Resources: LEED Certification (page 39) OR, only the CFC LEED section. Details on the Refrigeration cycle, Chillers from Carrier Corp, and LEED CFC Calculator from Trane in MS Excel format.
Please submit your answers on paper.
Extra Credit: Due4/3/2008 (Max 5 points on Exam 1)
In the attached child page create a narrative with appropriate figures/tables describing how projected climate change will influence one aspect of the environmental "status quo" in the State of Maine. Your narrative may include web links and must include appropriate references. Only one student per topic, claim your topic on the Impacts page.
Homework Assignment 7: Due 4/8/2008
Book Problems: page 242: 7, 12, 14, 19, 25, 29. Please turn in at the end of class.