Name that element! This element rules the computer age. You'll find it in most of Earth's soil, sand, and rocks--not to mention everything from PC chips to hairspray. What is it? Grab a periodic table and follow these eight clues to find out. Then turn the page to test your chem IQ. (Physical Science Chemistry).
Pop stars like Britney Spears use this mystery element to rock an audience. Mini microphones in recording equipment and headsets use quartz--the element's mineral form--to convert sound waves into electrical signals. The waves squeeze the quartz crystals in a mike to produce a voltage (change in electric charge)--it's called the piezoelectric effect. Wires feed the signal into speakers, blasting a singer's voice through a stadium.
GOT IT ALREADY? SCORE 100 POINTS. IF NOT, READ CLUE #2.
Today's watches tick off time using pure quartz crystal--smooth solids composed of atoms stacked in geometric patterns. The watch works like a microphone in reverse: When jolted by electricity from a battery, quartz vibrates up to millions of times per second at a constant rate, or frequency. This pulse, slowed to one beat per second, moves a watch's second hand. Quartz watches lose only one second every 10 years.
NABBED THE ANSWER? SCORE 80 POINTS. STILL GUESSING? TAKE THE NEXT CLUE.
This element puts the bounce in super-balls and Silly Putty. Together with the elements oxygen and carbon, it forms a polymer (repeating chain of molecules, or linked atoms). When polymer chains hook up, they form a compound with incredible stretch and bounce. This synthetic (human-made) rubber is stronger than natural rubber--it resists damage from heat and light, and won't dry out or crack over time.
GAME OVER ALREADY? SCORE 60 POINTS. STILL PLAYING? CHECK OUT CLUE #4.
Whether your hair flows or spikes, this element is your mane's best friend. A common ingredient in shampoos, conditioners, and gels, it makes hair soft, shiny, and easier to comb. That's because it coats hair strands and seals the hair cuticle--the outermost layer of the hair shaft that overlaps like shingles.
NAME IT NOW, SCORE 40 POINTS.
Think cell phones can't get any smaller? "A computer chip is basically a sliver of this element and other metals, the size of your thumbnail," says chemist Chuck Szmanda of Rohm and Haas. Like other metalloids found along the "stair-step" of the periodic table, this element is a semiconductor (conducts electricity when combined with other elements). As chips get smaller their electrical current generates more heat. This element can take the heat--so technology keeps shrinking.
HIT ON THE ANSWER? SCORE 20 POINTS. IF NOT, KEEP TRYING!
Scientists at the University of Southern California have invented a computer chip with this element to replace a damaged hippocampus, the part of the brain that stores new memories. The device is attached outside the skull where electrical signals from neurons (brain cells) are rerouted through two wire electrodes inserted into the damaged area. The chip stores the information and sends signals to the brain to replay the "memory." So far, it has only been tested in rats.
SCORE 10 POINTS IF YOU NAME THE ELEMENT WITH THE HELP OF SIX CLUES. STILL GUESSING? READ ON.
FROM PANE TO PAN
Staring out the window again? You're looking at this element. In its pure form this element absorbs light like a sponge, but when it bonds with two molecules of oxygen to form glass, light passes straight through it--making it appear transparent. Most glass is merely sand mixed with lime and ashes. The mix is melted and slowly cooled into hard sheets. When boron is added, the result is pyrex--glass used in baking pans that can withstand temperatures up to 500[degrees]C (932[degrees]F).
GUESS THE ELEMENT? SCORE 5 POINTS. IF NOT, TRY YOUR LAST CLUE.
This element spends most of its time at the beach. That's because sand is made in part from the weathering of granite rocks into quartz particles up to 4 mm (0.16 in.) in diameter. Quartz is the most abundant mineral compound on the planet, and this Group 14 element is the second most abundant element in Earth's crust.
STILL NO ANSWER? TURN TO PAGE 16.
ANATOMY OF AN ELEMENT
X Atomic number ?? Element symbol Name Element name X.XXX Average atomic mass
ATOMIC NUMBER equals the number of protons (positively charged particles) in an atom's nucleus, or center. Every element contains a different number of protons, and hence has a unique atomic number.
ATOMIC MASS equals the number of protons plus the number of neutrons found in a single atom of an element. The weight of an atom resides in its nucleus, which houses both protons and neutrons.
Did You Know?
* W.A. Marrison and J.W. Horton invented the quartz clock in 1927, but the quartz watch didn't appear until the 1970s. That's because quartz won't vibrate without an electrical pulse; it took many decades before batteries were small enough to fit in a portable timepiece. Early watches kept time by winding a mechanical spring and would run progressively slower as the spring unwound.
* Chemists at the University of California at San Diego have developed an explosives detector made from a string of silicon atoms. It's 2,000 times thinner than a single human hair and can detect the presence of TNT and picric acid, common components of terrorist weapons.
* Scientists hypothesize that silicon is part of the 1,440-mile diameter core at the center of Earth. Silicon lowers the density of iron under high pressure, which may explain the presence of a molten iron layer surrounding the solid metal core.
* As a component of clay, silicon is an important ingredient in earthenware ceramics and fine china. When wet, silicon makes clay a natural plastic (ability to change shape), but when heated it becomes hard as rock.
* Microphones made with silicon are 75 percent smaller on average than traditional microphones.
Technology: Silicone is a polymer that engineers have used to create a wide variety of products. What's another kind of polymers are used by industries today? Create a poster that includes a molecular diagram of your polymer and explains four ways it is used.
Critical Thinking: Try to envision a world without glass. Describe what your home would be like without glass.
Name That Element! Directions: Match each vocabulary word with the correct definition. -- 1. quartz a. resilient glass -- 2. semiconductor b. crystalline mineral -- 3. polymer c. outermost layer of hair -- 4. frequency d. change in electric charge -- 5. cuticle e. sometimes conducts electricity -- 6. Pyrex f. has metal and nonmetal properties -- 7. voltage g. measurement per unit of time -- 8. metalloid h. chain of molecules
Name that Element
1.b 2.e 3.h 4.g 5.c 6.a 7.d 8.f
The official Silly Putty Web site has a list of experiments to demonstrate the science of this silly silicone polymer: www.sillyputty.com/silly_science/silly_science.htm
For a detailed explanation of how a quartz watch works visit: electronics.howstuffworks.com/quartz-watch.htm
The Corning Museum of Glass has a page of Web links for teachers and students devoted to the art, science, history, and technology of glass: www.cmog.org/page.cfm?page=77
More on the brain-chip implant is available in this BBC news article: news.bbc.co.uk/2/hi/health/2843099.stm
This high-school textbook has some excellent pictures and descriptions of everyday uses of silicon: Chemistry: Concepts and Applications, Glencoe/McGraw-Hill, 2002
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|Date:||May 9, 2003|
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