CH217 - Homework

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h2.  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]                

h2. 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 | 1.45 \*10^7 J/year \\ | 1764 | 2.56 \*10^7kJ \\ |
| Andy | Laptop chargers | | | |
| Reuben | Televisions | | | |
| Erin | Hair Straighteners | 1.96 * 10^7 J/year | 966.7 | 3.45 \*10^7 kJ |
| 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 \\ | 1.281 x 10^5 kJ/year \\ | 176.4 \\ | 2.260 x 10^7 kJ/yr \\ |
| Josie \\ | Microwave \\ | 5.3 * 10^5 kJ/year\\ | 875 \\ | 4.6 * 10^8 kJ \\ |
| Trevor \\ | Gaming Console \\ | | | |
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, \\
InMotion \\ | 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/female-day*365 days/yr*960 females = 9.55E7kJ/yr
Total Male Usage per Year = 667 kJ/female-day*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

\| {color:black}{*}Room{*}{color} \| {color:black}{*}Brand{*}{color} \| {color:black}{*}Voltage (V)*{color} \| {color:black}{*}Current (A)*{color} \| {color:black}{*}Power (W)*{color} \|
| {color:black}1{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}2{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}3{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}4{color} | {color:black}Timex{color} | {color:black}120{color} | {color:black}0.05{color} | {color:black}6{color} |
| {color:black}5{color} | {color:black}Memorex{color} | {color:black}15{color} | {color:black}1{color} | {color:black}15{color} |
| {color:black}6{color} | {color:black}Sony{color} | {color:black}120{color} | {color:black}0.04{color} | {color:black}5{color} |
| {color:black}6{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}6{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}7{color} | {color:black}Sony{color} | {color:black}120{color} | {color:black}0.04{color} | {color:black}5{color} |
| {color:black}8{color} | {color:black}RCA{color} | {color:black}22{color} | {color:black}1{color} | {color:black}22{color} |
| {color:black}8{color} | {color:black}iPod{color} | {color:black}15{color} | {color:black}1.5{color} | {color:black}22.5{color} |
| {color:black}9{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}9{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}9{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}10{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}11{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}12{color} | {color:black}Sony{color} | {color:black}120{color} | {color:black}0.04{color} | {color:black}5{color} |
| {color:black}13{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} |
| {color:black}14{color} | {color:black}Sony{color} | {color:black}120{color} | {color:black}0.04{color} | {color:black}5{color} |
| {color:black}15{color} | {color:black}Memorex{color} | {color:black}120{color} | {color:black}0.04{color} | {color:black}5{color} |
| {color:black}16{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | {color:black}0{color} | |


*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 non-owners): 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*
----
Josie Thiele, Microwave Oven
| | Brand | Voltage (V) | Current (A) | Power (W) |
| 1 | Cuisinart | 120 | 8 | 1000 |
| 2 | | 120 | 8 | 1000 |
| 3 | GE | 120 | 9 | 1100 |
| 4 | | 120 | 9 | 1100 |
| 5 | LG | 120 | 13 | 1500 |
| 6 | | 120 | 13 | 1500 |
| 7 | | 120 | 13 | 1500 |
| 8 | Sharp | 120 | 9 | 1100 |
| 9 | | 120 | 9 | 1100 |
| 10 | Frigidaire | 150 | 6 | 900 |
| Average | | | | 1180 |
Assuming that there is one microwave per room (and each room has 2 people in it), and each room uses it for 20 minutes a day. 

*Yearly Average Power Use per microwave*


1180J/s*60s/min*20min/day*365day/yr*1kJ/1000J=5.2*10^5kJ/yr

*Annual Campus Power Use*


Assuming there is one per room, \~875 rooms

5.2*10^5kJ*875rooms=4.6*10^8kJ/yr

\*Erin Schnettler-Hair Straightners
| Sample | Brand | Voltage (V) | Power (W) |
| 1 | Emperor | 110V | 200W |
| 2 | Solia | 110V | 58W |
| 3 | Sedu | 110V | 72W |
| 4 | Solia | 110V | 58W |
| 5 | CHI | 110V | 35W |
| 6 | Sedu | 110V | 72W |
| 7 | Conair | 120V | 36W |
| 8 | Solia | 110V | 58W |
| 9 | Hot Tools | 110V | 170W |
| 10 | Solano | 110V | 135W |
| Avg. || 89.4W |

\--Average Energy Consumption per year assuming 10 minutes of daily use
89.4J/sec*(60sec/min)*(10min/day)*(365days/year)=19578600 J/year

\--Avg. Energy Consumption per year assuming that use is limited to all females on campus:
19578600 J * 1,764 students * .548 =3.454*10^10 J (1 kJ/1000 J) = 3.45*10^7 kJ/year

\_______________________________________________________________________________________________ 

*Greg Klein: Coffee Makers*

| | Brand | Voltage (V) | Current (A) | Power (W) |
| 1 | Mr. Coffee | 120 | 7.5 | 900 |
| 2 | | 120 | 7.5 | 900 |
| 3 | Black and Decker | 120 | 10 | 1200 |
| 4 | Cuisinart | 120 | 13.833 | 1660 |
| 5 | | 120 | 13.833 | 1660 |
| 6 | Cuisinart | 120 | 9.166 | 1100 |
| 7 | | 120 | 9.166 | 1100 |
| 8 | Hamilton Beach | 120 | 7.5 | 900 |
| 9 | Hamilton Beach | 120 | 12 | 1140 |
| 10 | | 120 | 12 | 1140 |
| Average || 1812.5 |

*Assuming about one in ten students has a coffee maker:*

0.1	x 1764 students = 176.4 students

*Average yearly power consumption, assuming 5 minutes daily use:*

1170 J / sec x 60 sec / min * 5 min x 365 = 1.281 x 10^8 J / year

*Total power consumption for the campus:*

1.281 x 10^8 (J / year x students) x 176.4 students = 2.260 x 10^10 J / year

*2.260 x 10^7 kJ / year*

----
*Andy Oakes, Laptop Chargers*

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\-->\| Sample \| Brand \| Voltage \| Current \| Power \|
| 1 | Macbook | 16.5V | 3.65A | 60W |
| 2 | Macbook Pro | 16.5V | 3.65A | 60W |
| 3 | Dell Latitude | 19.5V | 3.34A | 65W |
| 4 | Dell Inspiron | 19.5V | 3.34A | 65W |
| 5 | Macbook Pro | 16.5V | 4.6A | 85W |
| 6 | HP Compaq | 19V | 4.74A | 90W |
| 7 | Macbook Pro | 16.5V | 3.65A | 60W |
| 8 | Macbook | 16.5V | 3.65A | 60W |
| 9 | Dell Inspiron | 19.5V | 3.34A | 65W |
| 10 | Gateway NV | 19V | 4.74A | 90W |
| Average | | | | 70W |

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
----
Sarah Dallas-\- Cell Phone Chargers

|| sample || brand \\ || voltage (V) \\ || current (A) \\ || Power (W) \\ ||
| 1 \\ | LG \\ | 5 \\ | 1 \\ | 5 \\ |
| 2 \\ | BlackBerry \\ | 5 \\ | 0.7 \\ | 3.5 \\ |
| 3 \\ | BlackBerry \\ | 5 \\ | 0.7 \\ | 3.5 \\ |
| 4 \\ | Samsung \\ | 5 \\ | 0.7 \\ | 3.5 \\ |
| 5 \\ | LG \\ | 5.1 \\ | 0.7 \\ | 3.57 |
| 6 \\ | LG \\ | 5.1 \\ | 0.7 \\ | 3.57 \\ |
| 7 \\ | Motorola \\ | 5 \\ | 0.55 \\ | 2.75 |
| 8 \\ | LG \\ | 4.8 \\ | 0.9 \\ | 4.32 |
| 9 \\ | LG \\ | 5.1 \\ | 0.7 \\ | 3.57 |
| 10 \\ | BlackBerry \\ | 5 \\ | 0.7 \\ | 3.5 |
| Average \\ | | | | 3.678 |
1764 chargers on campus, because every student has a cell phone

Assume they are used by everyone for 3 hours a day every day of the year

3.678 J/sec * 60 sec/min * 60 min/hr * 3 hr/day * 365 days/yr = *1.45E7 J/yr*


Power*#of chargers >> 1.45E7 * 1764 = 2.56E10 J >> *2.56E7 kJ*
----
Trevor Poole - Game Consoles


|| Sample # || Brand || Use (min/week) || Voltage (V) || Current (A) || Power (W) ||
| 1 | Xbox 360 | 120 | 12 | 12.1 | 150 |
| 2 | None | 0 | 0 | 0 | 0 |
| 3 | None | 0 | 0 | 0 | 0 |
| 4 | Xbox 360 | 60 | 12 | 14.2 | 175 |
| 5 | None | | | | |
| 6 | Wii | 90 | 12 | 3.7 | 33 |
| 7 | None | 0 | 0 | 0 | 0 |
| 8 | Xbox 360 | 90 | 12 | 14.2 | 175 |
| 9 | Wii | 90 | 12 | 3.70 | 33 |
| 10 | None | | | | |

40% of rooms total have game consoles, however all surveyed were male.  1764 total students * (.4 (males on campus) * .5 (males with game consoles)) =.2 total, or 353 game consoles on campus

Used for an average of 90 minutes per day

113.2J/s * 60seconds/minute * 60 mins/hour * 1.5 hours/ day * 365 days/year = 223,117.2 kJ per year per console.

223,117.2 kJ * 353 consoles = 78,760,371.6 kJ
----
Amy Holmen, mini fridges
|| Sample \\ || Brand \\ || Votage (V) \\ || Current (A) \\ || Power (W) \\ ||
| 1 \\ | GE \\ | 120 \\ | 0.75 \\ | 90 \\ |
| 2 \\ | MagicChef \\ | 115 \\ | 1.2 \\ | 138 \\ |
| 3 \\ | MagicChef \\ | 115 \\ | 1.3 \\ | 149 \\ |
| 4 \\ | Sanyo \\ | 120 \\ | 1.0 \\ | 120 \\ |
| 5 \\ | Haier \\ | 110 \\ | 1.1 \\ | 121 \\ |
| 6 \\ | Danby \\ | 120 \\ | 0.85 \\ | 102 \\ |
| 7 \\ | none \\ | \-\- \\ | \-\- \\ | \-\- \\ |
| 8 \\ | GE \\ | 120 \\ | 0.75 \\ | 90 \\ |
| 9 \\ | none \\ | \-\- \\ | \-\- \\ | \-\- \\ |
| 10 \\ | MagicChef \\ | 115 \\ | 1.2 \\ | 138 \\ |
| | | | AVERAGE \\ | 118.5 \\ |
*Yearly Average power use per fridge*

Let us assume that the fridge is plugged in and running all day for 9 months of the year (our school year)


118.5 J/sec * 60 sec/1 min * 60 min/1hr * 24 hr/day * 270 day/year= 2.7 \*10^6 kJ per year per fridge

*Annual Campus Power Use*

Assume that 80% of rooms have a fridge, so 750 rooms * 0.80= 600 fridges on campus

2.7*10^6 kJ/year/fridge * 600 fridges= 1.62*10^9 kJ/year

----
h2. Homework 3\- The basics of biomass (due 2/26/2010)


Some Links to get things started

[http://blogs.middlebury.edu/biomass/]

[http://www.colgate.edu/DesktopDefault1.aspx?tabid=4354]

[http://www.fs.fed.us/woodybiomass/state.shtml]

[^biomass_memo_071708.pdf]

[^tb197.pdf]

[http://www.aashe.org/wiki/climate-planning-guide/carbon-offsets.php]



[http://alethonews.wordpress.com/2010/01/12/up-in-smoke/]


Questions to consider:
\\

1) It is generally assumed that Maine is harvesting wood at a rate equal to the annual growth rate.&nbsp;&nbsp; Is this true?&nbsp; What are Maine’s requirements for sustainable growth?
\\

2) If question one is true, how does a biomass plant meet the additionally principle for carbon neutrality?&nbsp; Do we have additional biomass capacity in Maine?

3) Using Middlebury’s wood consumption as a guide, how many acres of forest are required to meet the fuel requirements of the proposed biomass plant at Colby?&nbsp;&nbsp;How many acres of forest will need to be harvested to meet Colby’s fuels supply in a sustainable fashion?

A) Divide the class into groups of four and claim decide which group will address which question.

B) Starting with the resources provided at the beginning of this question, generate an annotated bibliography of sources to help answer your question.

C) Generate two figures diagramming the material flows used to help answer your question.

D) For class on Friday, 2/26.&nbsp;&nbsp; Be prepared to present your two figures and your strategy for answering your group question.