Chemistry 151:  Pick & Choose Homework Assignments,    Instructor:  Ken Costello
Each assignment is worth 5 points.  You do not do all of these; just pick 15 that best suits you. You can do two extra for 7pts extra credit.
Turn in assignments as you finish them.  Final day for turning in assignments is May 4.
   
Assignment Comments & Directions
1. Textbook:  On page 320 (318, 3rd edition) are sizes of the elements with and without a charge.  When we write Mg  + O2 --> 2MgO, we should write              Mg + O2 --> 2MgO,  why? A problem with chemistry education is that it uses the symbols for elements too much.  In doing so, much truth about elements is overlooked. 
2. Textbook:  On page 311 (p 309 in 3rd edition), the units of MJ are used. I don't think it means Michael Jordan or marijuana.  What is the textbook referring to? Abbreviations are always a bit risky because they can have multiple meanings. 
3. Textbook:  On page 311 (309), they talk about the energy to remove electrons  (ionization).  It says it takes 37.83 MJ/mol to strip off carbon's fifth electron.  If a mole of these electrons came back to the carbon but pass through a 50 watt bulb, how many days could that bulb burn? 1watt=1joule Separating electrons from protons takes a lot of energy. A  mole of electrons (about the weight of your breath) separated from a mole of protons (1 gram) can move mountains. For example, locking down one mole of protons here in Mesa and placing a mole of electrons on the back side of the Great Pyramid of Giza could easily drag the pyramid to Mesa.
4. Textbook:  We know electrons repels electrons.  If you have 10 electrons filling the d-orbital you would have something that looks like figure "I" on page 282 (280 in 3rd edition).  How would you describe it? Also give the quantum numbers for each of those 10 electrons. Electrons do an amazing job of staying away from each other, while at the same time crowding in to get as close as possible to the nucleus.
     
5. Internet: Visit the site listed and describe what change you see as electrons go from 2p orbitals through 7p orbitals.  Click on the the 2p, 3p, 4p, etc on the left side of the screen.  Also, how would describe the 4f electrons, and the 6g electrons? Beauty and science together.  Electron orbitals are often seen as more beautiful than flowers. This site shows that: http://winter.group.shef.ac.uk/orbitron/AOs/7g/index.html This takes you to the page with the 7g electron orbitals.  Note that one electron creates all of those globular regions.
6. Internet: Go to the website listed try to make the Lewis structure for ammonia, water, ethanol, carbon dioxide, molecular nitrogen, and the sulfate ion.  Click "check structure" to see if correct.  If so, copy the structure to paper to turn in. This website gives you practice at making Lewis structures.  http://www.stolaf.edu/depts/chemistry/courses/toolkits/121/js/lewis/   Click on the pop-down box that lets you choose different compounds.  When a compound appears, click to add electrons or bonds to satisfied the octet rule and to use all valence electrons. 
7. Internet:  On the right side report what oxides of phosphorus are given.  On the left side, click History and report how phosphorus was first prepared.  Then click Biology and report how much phosphorus is in a 100 kg(220 lb) body. Now click on Reactions & report the reaction of phosphorus with oxygen. Webelements is a valuable resource for chemical data.  It's URL is http://www.webelements.com/  When you get there, choose phophorus on the Periodic Table.
8. Internet:  After reading the tutorial on the Web, answer the question about where does energy go.  In other words, we all use electricity and gasoline, where does that energy go after we've used it?  Also answer what devices produce ozone?  Finally, what does ozone smell like?  Energy will become more crucial to all of us.  Visit my Web page that covers energy.  http://www.chemistryland.com/CHM107/Energy/Energy.html
9. Internet:  At the Freeware (Free Stuff) page what is the first product listed?  Further down, what are the first 3 User's Guides listed?  At the top of the page is a link to Demo Movies.  Go to that page and find the link to "Chemical Drawing and Databasing"  On that page the first movie listed is Drawing a Cyclic Peptide.  Click the link to "View Online" or "Download Movie". Near the end of the movie it lists three things that Chemsketch does.  What are they? A lot of great free software is available for chemistry students.  Go to this website:  http://www.acdlabs.com  and look for the Downloads pop-down menu.  Choose the Freeware link.
10. Internet:  At the site listed, choose the Gases practice test.  How would you answer questions 1, 2, 5, & 7?  Now choose Reactions practice test and how would you answer 12, 15, & 20? Online help is available for those going into pharmacy and will be taking the PCAT exams.  Visti this site for some self asessment modules:  http://www.testprepreview.com/pcat_practice.htm
11. Ingredients: Look at the ingredients of bleach like Clorox (not the color-safe kind) and the ingredients of a product called Tilex Instant Mildew Remover and report the common active ingredient.  Also describe how you could save money by making your own Tilex. Some products are overpriced when you realize their ingredients.
12. Ingredients: The chemical name for Aspirin is acetyl salicylic acid.  Report which brand of anti-dandruff shampoo uses salicylic acid.   When aspirin decomposes, it forms acetic acid (vinegar) and salicylic acd.
13. Ingredients: Salicyclic acid is also used in acne soaps and for wart removal.  Report which brand of wart remover uses salicylic acid.   Salicylic acid has the ability to dissolve skin, which is why it is used in these products.
14. Wet Lab:  Place about 20 tablets of aspirin in a small pan of water and boil the water for a few minutes.  Turn off the heat and describe what you see and what you smell. Don't touch the water. When heated, Aspirin decomposes into acetic acid and salicylic acid.  Salicyclic acid from aspirin could be a cheap way of making your own anti-dandruff shampoo, wart remover, and soap for acne.
15. Environment:  What is the starting material for biodiesel?  How is it better than regular diesel? Wikipedia is one good source of info for this. As gas prices rise, people are looking for ways of cutting fuel costs.  If you drove a diesel vehicle, you might look into making your own biodiesel.
16. Environment: Ozone warnings are common here in the valley.  What is ozone and where is this ozone pollution coming from?  There is also what's called good ozone and bad ozone.  Where is good ozone? Ozone is also used as disenfectant, which tells you it has poisonous properties.
17.  Mythbusting:  1) A university student who drank too many Cokes died from carbon dioxide poisoning.  2) A mixture of Enfalac baby formula and dog food caused a toddler's stomach to explode. This site is great for resolving myths.  www.snopes.com    Use it to determine if the two myths listed are true or not.
18.  Mythbusting:  Coca-cola originally had cocaine in it and was original used as a medicine rather than a beverage.  Is this story true? www.snopes.com
19.  Mythbusting: Water boiled in a microwave oven can suddenly "explode." Is this  true?  What is claimed to cause the water to explode? http://hoaxbusters.ciac.org/HBInconsequential.shtml#hotwater  also www.snopes.com
20.  Mythbusting:  Aspartame (Nutrasweet/Equal) has been blamed for cancer, nervous disorders, seizures, and many other ailments.   Go to this site to see if research supports this claim.   www.greenfacts.org
21.  Mythbusting:  Is Global Warming true?  If so, how much temperature increase was there in the last century?  Has the snow and ice cover on the Earth decreased?  Has the level of the ocean risen? www.greenfacts.org
22.  Mythbusting: 1) Sodium lauryl sulfate, a substance commonly found in shampoo and toothpaste, poses a significant cancer risk to users of those products. 2) Adolescents have died huffing from cans of Dust-Off brand compressed air. For these two myths, check out www.snopes.com
23.  Mythbusting: Dihydrogen monoxide is claimed to be toxic. Visit  http://www.dhmo.org/ and learn about it and then see www.snopes.com to see if a student won a science fair reporting the dangers of 'dihydrogen monoxide.' www.dhmo.org and www.snopes.com   Is dihydrogen monoxide as dangerous as the web site claims?  Also, how true are some of their claims?
24. Mythbusting:  1)Reusing plastic water bottles causes them to break down into carcinogenic compounds.  2)Ordinary use of Canola oil is dangerous to consumers. Go to snopes to determine the validity of these 2 myths.  The Toxin category is where most of these are found.
25. Mythbusting:  1)Mold that forms in pancake mix can cause life-threatening allergic reaction.  2)Drug traffickers are hiding small amounts of ricin in methamphetamine labs to kill law enforcement officers For these two myths, check out www.snopes.com