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October, 2012 ® DEMYSTIFYING EVERYDAY CHEMISTRY OCTOBER 2012 Amazing Graphene Get Ready for Its Life- Changing Applications! p. 6 A Reversal of Fortune for Type 1 Diabetes, p. 9 Weather Myths: True or False? p. 14 www.acs.org/chemmatters Production Team Patrice Pages, Lead Editor Cornithia Harris, Art Director Therese Geraghty, Copy Editor Administrative Team Marta Gmurczyk, Administrative Editor Peter Isikoff, Administrative Associate NEWS Technical Review Seth Brown, University of Notre Dame David Voss, Medina High School, Barker, NY Teacher’s Guide William Bleam, Editor Check Out the ACS ChemClub Cookbook! Donald McKinney, Editor Erica K. Jacobsen, Editor Ronald Tempest, Editor Afternoon snack attack. A cookie craving hits. You’re out of store-bought cookies, so you Susan Cooper, Content Reading Consultant decide to bake your own. You fl ip through a cookbook; Grandma Button’s Favorite Molas- David Olney, Puzzle Contributor ses Cookies sound good. A quick look at the list of ingredients shows what you will need Education Division Mary Kirchhoff, Director to grab—a matured ovum with yolk overlaid with albumen proteins from Gallus domesticus Terri Taylor, Assistant Director, K–12 Science female? Dried and powdered rhizome of Zingiber officinale? What? Policy Board This recipe is one of dozens that you will fi nd in the recently pub- Ami LeFevre, Chair, Skokie, IL Shelly Belleau, Thornton, CO lished American Chemical Society (ACS) ChemClub cookbook. The Steve Long, Rogers, AR Mark Meszaros, Rochester, NY Club from East Syracuse–Minoa High School in East Syracuse, NY, Scott Goode, Columbia, SC submitted the recipe described above. To successfully make the ChemMatters (ISSN 0736–4687) is pub- cookies, the reader needs to translate “science speak” into the lan- lished four times a year (Oct, Dec, Feb, and April) by the American Chemical guage of the kitchen, connecting chemistry with cooking. Society at 1155 16th St., NW, Washington, DC 20036–4800. Periodicals postage paid During the 2011–2012 school year, ACS ChemClub members at Washington, DC, and additional mail- experimented in the kitchen and submitted their favorite recipes. ing offices. POSTMASTER: Send address changes to ChemMatters Magazine, ACS In the cookbook, these range from family favorites to recipes Office of Society Services, 1155 16th St., NW, Washington, DC 20036. representing different ALAN HENRY/BLAIR JANINE TAYLOR/CAN STOCK PHOTO Subscriber Information cultures to food-based activities Prices to the United States, Canada, and conducted in the laboratory. Mexico: $14 per subscription. Inquire about bulk, other foreign rates, and back issues Each recipe includes information about at the ACS Office of Society Services, 1155 16th St., NW, Washington, DC 20036; related food chemistry. For example, if you 800-227-5558 or 202-872-6067 (fax). make Guacamole de Rancho (submitted by Information is also available online at: www.acs.org/chemmatters. Donna High School in Donna, Texas), you will The American Chemical Society assumes learn why we cry when chopping onions. It no responsibility for the statements and opinions advanced by contributors. Views EWA HENRY (ACS CHEMCLUB COOKBOOK, P. 65) says that chopping onions produces a chemi- expressed are those of the authors and do cal called propanethial S-oxide (C3H6OS) that not necessarily represent the official position of the American Chemical Society. The activ- vaporizes easily. Its water-soluble vapors can react with the liquid in your eyes, causing the ities in ChemMatters are intended for high school students under the direct supervision eyes to burn and itch. of teachers. The American Chemical Society cannot be responsible for any accidents or The ACS ChemClub cookbook is available for purchase at the ACS Store online at: injuries that may result from conducting the https://www.store.acs.org. Proceeds help to support the ACS ChemClub program. activities without proper supervision, from not specifically following directions, from ignoring the cautions contained in the text, or from not following standard safe labora- tory practices. All rights reserved. No part of this publi- cation may be reproduced, stored in a Demystify Everyday Chemistry with retrieval system, or transmitted in any form by any means, now known or later devel- oped, including, but not limited to: elec- tronic, mechanical, photocopying, record- ing, or otherwise, without prior permission from the copyright owner. Requests for permission should be directed in writing to Connect your chemistry lessons to students’ everyday lives ChemMatters, American Chemical Society, and promote scientifi c literacy and chemistry. 1155 16th St., NW, Washington, DC 20036– 4800; 202-833-7732 (fax). will be delivered to your home or classroom four times a year for just $16. Get our 25-year collection on CD for only $30! © Copyright 2012 American Chemical Society Canadian GST Reg. No. 127571347 Printed in the USA Subscribe by calling 1-800-227-5558 or accessing www.acs.org/chemmatters www.acs.org/chemmatters ® Vol. 30, No. 3 OCTOBER 2012 DEPARTMENTS Did You Know? 4 Noble Gases: Xenon Reacts! Chemistry of Carbon: Going Up! Open for Discussion: Nanoparticles 5 By Barbara Sitzman and Regis Goode HTTP://M.PHYS.ORG/PARTICLES-SHAPES- Nanoparticles are clusters of a few hundred to a few thousand atoms that promise to change our lives in unique and useful ways. COPYRIGHT2007PHYSORG.COM. ALL RIGHTS RESERVED; METHOD_NEWS104677694.HTML 5 6 FEATURES Traducción en Graphene: The Next Wonder Material? 6 español By Michael Tinnesand disponible en Graphene, the thinnest known material, could be used to make foldable cell Internet phones, and fl exible solar panels, and devices that help people with spinal cord injuries regain use of their limbs. CRUNCHWEAR.COM 9 Diabetes: Tiny Particles to the Rescue 9 By Roberta Baxter People with type 1 diabetes—many of them teenagers—need to check their blood sugar fi ve to seven times per day and give themselves an average of fi ve Check out the video podcast about graphene at: insulin injections every day. Relief from this demanding routine may be on the www.acs.org/chemmatters way, thanks to scientists who are working on a vaccine based on nanoparticles. (Un)Stuck on You 12 PHOTOS.COM By Renée Heiss Static cling causes your clothes to cling to your body and clothes to stick to one 12 14 another after being washed and dried. So, how do you get rid of static cling? A type of fabric called a nanotextile may be the answer. Weather Folklore: Fact or Fiction? 14 By Brian Rohrig Many expressions about the weather have been passed down through the ages. Are any of them true? We look at the science (and chemistry) behind four such expressions… and learn about how the weather works! PHOTOS.COM “Chance Favors the Prepared Mind”: Great Discoveries PHOTOS.COM in Chemistry 17 By Gail Kay Haines Three scientifi c discoveries—those of urea, radioactivity, and buckyballs—have transformed our modern world. We tell you the intriguing personal stories of the scientists who, against all odds, made these remarkable discoveries. FREE! TEACHER’S Guide! Find a complete teacher’s guide for this issue at: www.acs.org/chemmatters ON THE COVER: COURTESY OF TOUCHBIONICS.COM ChemMatters, OCTOBER 2012 3 DID YOU KNOW?...DID YOU KNOW?... Noble Gases: Xenon Reacts! nreactive, inert, does Canada, formed an interesting “Unot form compounds.” precipitate with a deep red color. Until 50 years ago, that was the He and a graduate student began description found in chemistry investigating the compound and textbooks for the noble gases, discovered that it was a com- a group of six elements found bination of an anion, platinum – on the right side of the periodic hexafluoride (PtF6 ), and a cation + table—helium, neon, argon, (O2 ). krypton, xenon, and radon. Unlike every other oxygen- Noble gases are mono- containing compound, in which atomic—they consist of a single oxygen is the negatively charged atom—because they have full ion, in this red solid, oxygen is HTTP://EN.WIKIBOOKS.ORG/WIKI/STRUCTURAL_BIOCHEMISTRY/NOBLE_GASES outer electronic shells, which positively charged. The reason makes them unlikely to gain or for this difference is that the this idea. He built a glass con- He initially assigned the lose electrons. Chemists thought platinum hexafluoride ion is more tainer with two parts to hold a orange-yellow solid as XePtF6, + they would not ever react, but electronegative than oxygen. different gas in each, with a seal a simple salt containing Xe and – a young chemist proved them Bartlett began to think that between the two parts. PtF6 . Later studies have shown wrong and introduced a whole if platinum hexafluoride could “when I broke the seal that the actual solid is more com- new set of compounds made by pull electrons away from oxy- between the red PtF6 gas and plex, but all agree that Bartlett reacting noble gases. gen atoms, it might as well pull the colorless xenon gas, there had succeeded in preparing the In 1958, Neil Bartlett, a lecturer electrons away from xenon, one was an immediate interaction, first chemical compound of a in chemistry at the University of the noble gases. So, Bartlett causing an orange-yellow solid to noble gas. of British Columbia, Vancouver, planned an experiment to test precipitate,” he later wrote. —Roberta Baxter Chemistry of Carbon: Going Up! ou step into an elevator, the carry large loads. Such a strong The carbon atoms in a nano- Ydoors close, and the eleva- cable could be made with a type tube link together in hexagons, tor begins to move. Sounds like of material called a nanotube, giving it a rigid structure that is a routine occurrence, except that which is a sheet of carbon graph- stronger than steel but weighs the next stop for this elevator is ite rolled into a cylinder. Nano- much less than steel. space.
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