1. The Inner Workings of Old and Modern Refrigerators Eric Abercrombie Levi Algozino E-Design 100 Section 9 Pennsylvania State University http://upload.wikimedia.org/wikipedia/commons/3/36/ExpensiveR efrigerators.JPG

2. Refrigeration is the process of removing heat from an enclosed space generally by evaporating and condensing a substance (usually a CFC gas). http://firstcoastac.com/faq/freon/

3. Several Types of Gases have been used in refrigeration systems as chemists discover more efficient systems. http://upload.wikimedia.org/wikipedia/commo ns/thumb/3/34/Sulfur_dioxide.svg/467px- Sulfur_dioxide.svg.png http://www.gcsescience.com/Ammonia-Molecule.gif http://upload.wikimedia.org/wikipedia/common s/thumb/3/30/Methyl_Chloride.svg/261px- Methyl_Chloride.svg.png Almost all have been phased out due to harmful effects to either the surrounding area or the o-zone layer.

4. Cooling both a freezer and a refrigerator involves the coolant previously mentioned (usually Freon), getting put through a short process. 1: Compression 2: Release of heat 3: Expansion 4: Cooling of unit 5: Back to compression http://www.realsimple.com/food-recipes/tools- products/appliances/how-does-refrigerator- work-00100000087962/index.html

5. The interior refrigeration system Substance vaporized Heat absorbed Substance liquefied http://www.energyquest.ca.gov/how_it_works/refrig erator.html

6. If a temperature is set on a refrigerator, the cycle just continues until the desired temperature is reached. When a special thermometer detects that the fridge has reached the proper temperature, it simply shuts off the motor and the refrigeration cycle is halted. http://www.tmchallcrest.com/fridge-freezer-indicators.php

7. Works Cited: http://www.energyquest.ca.gov/how_it_works/refrigerator.html http://firstcoastac.com/faq/freon/ http://inventors.about.com/library/inventors/blrefrigerator.htm http://www.realsimple.com/food-recipes/tools-products/appliances/how- does-refrigerator-work-00100000087962/index.html http://www.realsimple.com/food-recipes/tools-products/appliances/how- does-refrigerator-work-00100000087962/index.html http://home.howstuffworks.com/refrigerator4.htm