Homework Assignment 1: General Chemistry Review (due 2/8/2010)
 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 2/15/2010)
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 

example 
microwave 
3.73 * 10^4 kJ/year 
1077.1 
4.01 * 10^7 kJ 
Sarah 
Cell chargers 



Andy 
Laptop chargers 



Reuben 
Televisions 



Erin 
Hair Straighteners 



Rachael 
Lamps 
9.58 E7 J/yr 
1717 
1.65 E8 kJ 
Amy 
Refrigerators 



Devon 
Speakers 
6.93 * 10^7 J/year 
1235 
8.56 * 10^7 kJ 
Mike 
Electric Razors 
1.79 * 10^3 J/year 
706 
1.26 * 10^5 kJ 
Kimberly 
clocks 
1.36 x 10^8 J/yr 
752 
2.4 x 10^8 kJ/yr 
Greg 
Coffee Maker 



Josie 
Microwave 



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 ....
_______________________________________________________________________________________________
Example, Blow Drier

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
Electric Razors
Sample # 
Brand 
Use (min/week) 
Voltage (J/c) 
Current (c/sec) 
Power (J/sec) 

1 
Braun 
10 
12 
0.400 
4.8 
2 
Braun 
12 
12 
0.400 
4.8 
3 
No Razor 




4 
No Razor 




5 
No Razor 




6 
Phillips Norelco 
7 
15 
0.420 
6.3 
7 
Phillips Norelco 
12 
15 
0.420 
6.3 
8 
No razor 




9 
No razor 




10 
No razor 




Average 
40% of student body 
10.25 


5.6 
Average Energy Consumption:
5.6 J/sec * 60 sec/min * 10.25 min/week * 52 weeks/year = 1.79 * 10^3 J/year
Assuming only males use electric shavers
1.79 * 10^3 J/razor/year * 1764 students * 0.40 razors/student * 1J/1000kJ = 1.26 * 10^5 kJ/year
Devon McIntyre, iPod/Computer Speakers
Sample # 
Brand 
Voltage (V) 
Current (A) 
Power (W) 

1 
Altec Lansing, 
100  240 
0.8 
80 
2 
Logitech 
120 
0.525 
63 
3 
Bose 
120 
0.16 
19.2 
4 
Bose 
120 
0.16 
19.2 
5 
JBL 
120 
0.183 
22 
6 
JBL 
120 
0.183 
22 
7 
JBL 
120 
0.183 
22 
8 
Klipsch 
100  240 
max 1.5 
150 
9 
iSymphony 
120 
0.9 
108 
10 
JBL 
120 
0.183 
22 
Average 



52.74 
Average energy consumption in a year assuming speakers are used 1 hour per day:
52.74 J/sec * 60 sec/1 min * 60 min/1 day * 365 days/1 year = 6.93 E7 J/year
Colby students total – 1838
% Colby students on campus – 96%
Total Colby students on campus – 1764
Assume 70% of students have speakers – 1764 * .70 = 1235 students with speakers on campus
1235* * * 6.93 E7 J = 8.56 E10 J = 8.56 E7 kJ/year
_______________________________________________________________________________________________
Rachael Mack: Lamps

Brand 
Voltage (V) 
Current (A) 
Power (W) 
1 
Walmart 
120 
0.5 
60 
2 

120 
0.33 
40 
3 
Your Zone 
120 
0.33 
(40*5 bulbs) 200W 
4 

120 
0.33 
40 
5 
Jansjo 
120 
0.09 
10.8 
6 
Jansjo 
100 
0.09 
0.09 
7 
Walmart 
120 
0.12 
14 
8 

120 
0.5 
60 
9 

120 
0.33 
40 
10 
Walmart 
120 
0.12 
14 
Average 



48.78 
Assuming there is on average one lamp per person, and each person uses it daily for about 1.5 hours. (Approximately 93% of the total student body lives on campus – 1717 students.)
48.78 J/s * 60 s/min * 90 min/day * 365 day/yr = 9.61 E7 J/yr
9.61 E7 J/yr * 1717 students = 1.65 E8 kJ/yr
_______________________________________________________________________________________________
*Reuben Biel, Television*
Room No 
Brand 
Volt (V) 
Current (A) 
Wattage (W) 
Time (hrs_used/day) 
Occupants 
Gender 
kJ Used per Room per Day 
kJ Used per Individual per Day 
1 
Sylvania 
120 
0.44 
53 
0.57 
3 
M 
109.0285714 
36.34285714 
2 
Emerson 
120 
0.5 
60 
1 
2 
F 
216 
108 
3 
 
0 
0 
0 
0 
2 
M 
0 
0 
4 
Orion 
120 
0.92 
110 
1 
2 
F 
396 
198 
5 
Olevin 
120 
1 
100 
1.5 
3 
M 
540 
180 
6 
 
0 
0 
0 
0 
2 
F 
0 
0 
7 
 
0 
0 
0 
0 
3 
M 
0 
0 
8 
Emerson 
120 
0.46 
55 
1 
2 
F 
198 
99 
9 
Magnavox 
120 
2 
240 
0.57 
1 
M 
493.7142857 
493.7142857 
10 
Magnavox 
120 
0.33 
40 
5 
1 
M 
720 
720 
11 
RCA 
120 
0.46 
55 
1.5 
1 
F 
297 
297 
12 
LG 
120 
1.25 
150 
6 
1 
M 
3240 
3240 
13 
Insignia 
120 
0.58 
70 
0.5 
0.5 
F 
126 
 
13A 
LG 
120 
1.25 
150 
2 
0.5 
F 
1080 
 
13 Total 

0 
0 
0 
0 
1 
F 
0 
1206 
14 
 
0 
0 
0 
0 
1 
F 
0 
0 
Assuming that Televisions only draw energy while being used (false assumption so is an underestimate of actual usage):
Average Usage per Female per Day (including those without TVs): 273 kJ/day
Average Usage per Male per Day (including those without TVs): 667 kJ/day
If there are approx. 960 females (54.8%) and 790 males on campus (Total 1750 students), then:
Total Female Usage per Year = 273 kJ/femaleday*365 days/yr*960 females = 9.55E7kJ/yr
Total Male Usage per Year = 667 kJ/femaleday*365 days/yr*790 males = 1.92E8kJ/yr
Total Energy Usage per Year = 9.55E7kJ/yr + 1.92E8kJ/yr = 2.88E8kJ/yr
Kimberly Bittler, Electric alarm/radio clocks
 Room  Brand  Voltage (V)  Current (A)  Power (W) 
1 
0 
0 
0 
0 

2 
0 
0 
0 
0 

3 
0 
0 
0 
0 

4 
Timex 
120 
0.05 
6 

5 
Memorex 
15 
1 
15 

6 
Sony 
120 
0.04 
5 

6 
0 
0 
0 
0 

6 
0 
0 
0 
0 

7 
Sony 
120 
0.04 
5 

8 
RCA 
22 
1 
22 

8 
iPod 
15 
1.5 
22.5 

9 
0 
0 
0 
0 

9 
0 
0 
0 
0 

9 
0 
0 
0 
0 

10 
0 
0 
0 
0 

11 
0 
0 
0 
0 

12 
Sony 
120 
0.04 
5 

13 
0 
0 
0 
0 

14 
Sony 
120 
0.04 
5 

15 
Memorex 
120 
0.04 
5 

16 
0 
0 
0 
0 

Number of students with alarm clocks:
9/21 students in the survey = 43 % x ~1750 students on campus = 752 students
Average power use of alarm clocks: 10.0 W
Total Average power use (including nonowners): 4.3 W
Yearly Average Power Use per student:
4.3 J/sec x 60 sec/min x 60 min/hr x 24 hr/day x 365 day/yr = 1.36 x 10^8 J/yr
Campus Power use:
1.36 x 10^8 J/yr x 1750 students = 2.40 x 10^11 J/yr x 1 kJ/1000 J = 2.40 x 10^8 kJ/yr