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

1. Get a General Chemistry text that you may use as a reference for the semester.
2. 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

Alarm Clocks

Amy

Refrigerators

Devon

Speakers

Mike

Electric Razors

total

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

Voltage (J/c)

Current (c/sec)

Power (J/sec)

1

2

6

Phillips Norelco

15

0.420

6.3

7

Phillips Norelco

15

0.420

6.3

Average =