Objectives
Prior to the day of the event, students will research a halogenated polycyclic pesticide from the following list and construct its ball and stick model. Note whether the use of the insecticide has been banned and why. The model must be brought to the competition already built and will be judged as to how well it accuracy represents the molecule. Be prepared to answer questions orally about your model. The list of insecticides includes: Aldrin, Chlordane, Heptachlor, Dieldrin, Endosulfan, Mirex and Kepone.
On the day of the event, students will use online resources to provide written answers to four questions about the chemical and physical properties of the molecule.
Guidelines
A team of two or three students must complete this event.
This event is to be completed in 25 minutes.
Before the day of the event, the team will make their molecular model using low-density Styrofoam balls and wooden skewers. Low density Styrofoam balls crumble when rubbed together. They may be purchased at a crafts store, such as Michaels. Use different sized Styrofoam balls to represent the relative sizes of atoms and paint them according to the color code below. The maximum size permitted is 3-inch balls. Wooden skewers and glue are to be used for the bonds. Wooden skewers may be found at craft stores (ex: Michaels) or at a supermarket (ex: Shoprite). No other materials other than Low Density Styrofoam balls, Paint, Wooden Skewers and Glue are permitted!
Use black for carbon, yellow for hydrogen and red for oxygen. Most spray paints will cause Styrofoam to denature ("melt"). Styrofoam spray paint may be found at craft stores that sell Styrofoam balls (ex: Michaels).
In order to provide written answers to their four questions, each team will be provided with one computer with access to the Internet and resource books to aid in your search.
Sample questions:
Sample questions from NJCO 2008
The following are some of the databases that will be available to you:
| Chemfinder | http://www.chemfinder.com | This free database
includes: (REGISTRATION IS REQUIRED)
|
| Google Scholar |
http://scholar.google.com | A database of scholarly articles in a wide range of fields |
| Medline | http://www.ncbi.nlm.nih.gov/entrez/ | A database of 14,000,000 scholarly biomedical articles |
| Scirus | http://www.scirus.com | A comprehensive science specific search engine (can limit to scholarly articles) |
| PubChem | http://pubchem.ncbi.nlm.gov | Provides information on biological activities of small molecules |
| Toxnet | http://toxnet.nlm.nih.gov | Database on toxicology, hazardous chemicals, environmental health, and toxic releases |
| SIRI Materials Safety Database Sheet Index | http://hazard.com/msds/index.php | A database of toxicological and physical property data |
| SRC Interactive Physical Properties Database | http://esc.syrres.com/interkow/physdemo.htm | Includes information on 25,000 substances. You must search by CAS registry number. |
| Chem ID Plus | http://chem.sis.nlm.nih.gov/chemidplus/ | Database of over 380,000 chemicals, synonyms, structures, regulatory list information, and links to other databases |
| United States Patent Database | http://www.uspto.gov/patft/index.html | Database of United States Patents |
At the completion of your session, you must submit your written answers to your questions.
Judging Criteria:
Notes:
Last Updated January 04, 2009