Name that element! Which element on the periodic table helps tame a dangerous virus, fights dandruff, and helps direct motorists? Follow these eight clues to find out. Then turn the page to test your chemistry IQ.CLUE 1 GOT IT ALREADY? SCORE 100 POINTS. IF NOT, READ CLUE #2. EUREKA! When Swedish scientist Jons Jacob Berzelius first encountered the mystery element in 1817, he thought it was the known element tellurium tellurium (tĕl  r`ēəm) [Lat.,=earth], semimetallic chemical element; symbol Te; at. no. 52; at. wt. 127.60; m.p. 450°C;; b.p. 990°C;; sp. gr. 6. (Te). He later realized that he'd made a new discovery. Small
amounts of this element are sprinkled throughout Earth's crust.
Usually, it's combined with other elements to form compounds. Even
though the mystery element is a nonmetal nonmetal, chemical element possessing certain properties by which it is distinguished from a metal. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and form negative ions and that its oxide is acidic. , it's often found in ores
(metal-containing rocks) of copper, silver, and other metals.
CLUE 2 NABBED THE ANSWER? SCORE 80 POINTS. STILL GUESSING? GO TO THE NEXT CLUE. BRIGHT AND SHINY Because the mystery element is usually found in copper ores, refineries need to remove it in order to yield pure copper--an element often used to make pots and pans. They use electrolysis electrolysis (ĭlĕktrŏl`əsĭs), passage of an electric current through a conducting solution or molten salt that is decomposed in the process. , a process that utilizes electric currents to break chemical bonds, to separate copper from the mystery element. This process also leaves refineries with large commercial supplies of the mystery element, which shares the same period (row) as copper. CLUE 3 GAME OVER ALREADY? SCORE 60 POINTS. STILL PLAYING? CHECK OUT CLUE #4. GO NUTS "[The mystery element] is essential for life," says Richard Glass, a chemistry professor at the University of Arizona (body, education) University of Arizona - The University was founded in 1885 as a Land Grant institution with a three-fold mission of teaching, research and public service. . One reason: It protects cells from damage that could lead to diseases like cancer. Most Americans get sufficient amounts of this element through their daily diet. However, eating large amounts of the element could be toxic to the body. Brazil nuts are so high in this element that some doctors suggest eating them only once in a while. CLUE 4 NAME IT NOW? SCORE 40 POINTS OTHERWISE, READ ON. PIPE CLEANER pipe cleaner, n a small, brushlike device used to clean the spaces between the teeth (used also for other purposes). It should not be inserted all the way between the teeth, but rather just far enough to massage the tissue and remove any plaque. Brass is an alloy, or mixed-metal product. In the past, most plumbing-supply manufacturers used brass that contained lead. Lead made the brass machinable so that it could easily be shaped into faucets and water pipes. The downside: Lead can get into drinking water drinking water supply of water available to animals for drinking supplied via nipples, in troughs, dams, ponds and larger natural water sources; an insufficient supply leads to dehydration; it can be the source of infection, e.g. leptospirosis, salmonellosis, or of poisoning, e.g. and cause health problems, including brain damage in children. Many manufacturers have replaced lead with an alloy of bismuth bismuth (bĭz`məth) [Ger. Weisse Masse=white mass], metallic chemical element; symbol Bi; at. no. 83; at. wt. 208.9804; m.p. 271.3°C;; b.p. about 1,560°C;; sp. gr. 9.75 at 20°C;; valence +3 or +5. and the mystery element. The result: Brass stays machinable, but without the health hazards. CLUE 5 HIT ON THE ANSWER? SCORE 20 POINTS. IF NOT, KEEP TRYING! HIV HIV (Human Immunodeficiency Virus), either of two closely related retroviruses that invade T-helper lymphocytes and are responsible for AIDS. There are two types of HIV: HIV-1 and HIV-2. HIV-1 is responsible for the vast majority of AIDS in the United States. FIGHTER In a recent study, patients infected with HIV (the virus that causes I AIDS) took pills containing the mystery element for 18 months. The result: The amount of the virus in their bloodstream remained unchanged. But for patients who didn't take the mystery-element pills, the HIV levels in their bodies increased. Barry Hurwitz, one of the researchers who conducted the study at the University of Miami This article is about the university in Coral Gables, Florida. For the university in Oxford, Ohio, see Miami University. The University of Miami (also known as Miami of Florida,[2] UM,[3] or just The U , explains: "[The mystery element] is like a lion tamer in the circus. It makes viruses tamer, less likely to replicate (multiply)." CLUE 6 SCORE 10 POINTS IF YOU NAME THE ELEMENT WITH THE HELP OF SIX CLUES. STILL GUESSING? READ ON COPY THIS Push the start button of a photocopier photocopier Device for producing copies of text or graphic material by the use of light, heat, chemicals, or electrostatic charge. Most modern copiers use a method called xerography. and bright light moves across the document that you want copied. The light reflects down to a drum, or surface inside the machine that's coated with the mystery element, which is photosensitive A material that changes when exposed to light. See photoelectric. . Since the element is sensitive to light, it helps the drum capture an image of your document. Toner powder then inks the image, which is transferred to blank paper to make a copy. CLUE 7 GUESS THE ELEMENT? SCORE 5 POINTS. IF NOT, TRY YOUR LAST CLUE. DANDRUFF dandruff, excessive flaking of skin from the scalp, apparent as dry or greasy diffuse scaling with variable itching. It is the sign of a skin disease, such as seborrhea or a fungal infection. FIGHTER As new skin cells grow, old cells slough off. On the scalp, skin cells normally turn over every 21 days. But for a person with dandruff, a condition that irritates the scalp, the cells regenerate twice as quickly. This causes the old cells to build up in clumps before falling off. A compound containing the mystery element and sulfur, which are members of the same group (column), helps slow cell growth, so it's used as an ingredient in antidandruff shampoos. CLUE 8 GAME'S OVER. NOW TURN TO PAGE 20. STOP AT RED The mystery element helps prevent traffic accidents. TO make a stoplight's red glass covering, glass manufacturers mix a batch of ingredients including sand, ash, and limestone. "If you want red-colored glass, you toss in some [of the mystery element]," says Richard Glass. After the batch is melted at temperatures greater than 1,425[degrees]C (2,600[degrees]F), the molten material is then cooled and shaped into a red glass covering. This traffic-stopping element has 34 protons. Anatomy of an Element X Atomic number ?? Element symbol Name Element name X.XXXX XXXX Army (Graphical Representation/Army) XXXX Fourex (Australian beer) XXXX Four X Level of Decontamination Average atomic mass KEY DEFINITIONS: 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 so has a unique atomic number. In a neutral atom, the number of protons and the number of electrons (negatively charged particles) are equal. ATOMIC MASS equals the number of protons plus the number of neutrons (uncharged particles) found in a single atom of an element. The atom's mass is in its nucleus, which houses both protons and neutrons. PDST-READING DISCUSSION Follow up your lesson with these post-reading questions: * Swedish chemist Jons Jacob Berzelius (1779-1848) is considered one of the fathers of modern chemistry. Besides discovering selenium selenium (səlē`nēəm), nonmetallic chemical element; symbol Se; at. no. 34; at. wt. 78.96; m.p. 217°C;; b.p. about 685°C;; sp. gr. 4.81 at 20°C;; valence −2, +4, or +6. , he also discovered cerium cerium (sēr`ēəm) [from the asteroid Ceres], metallic chemical element; symbol Ce; at. no. 58; at. wt. 140.12; m.p. 799°C;; b.p. 3,426°C;; sp. gr. 6.77 at 25°C;; valence +3 or +4. , silicon, and thorium thorium (thôr`ēəm) [from Thor], radioactive chemical element; symbol Th; at. no. 90; at. wt. 232.0381; m.p. about 1,750°C;; b.p. about 4,790°C;; sp. gr. 11.7 at 20°C;; valence +4. . In addition, he developed the chemical symbols used today. What are the chemical symbols for the elements selenium, mercury, silver, and gold? * Selenium is just one of many ingredients used to light dandruff. What causes dandruff? What makes a person more susceptible to developing dandruff? For information, visit this Web site from the Mayo Clinic: www.mayoclinic.com/health/dandruff/DS00456 CRITICAL THINKING: * After your class has read "Name That Element!" have each student come up with a question related to one of the eight clues that he or she doesn't know the answer to, but is curious to find out. Write all the questions on the board. Then have each student select a question besides his or her own to research and answer. Have students present the answers during the following class. CRDSS-CURRICULAR CONNECTIONS: HEALTH: You learned that selenium is essential for life. Research to find another element that is essential for the human body. Create a fact sheet about how the element helps the body function. RESDURCES * For more on Jons Jacob Berzelius, the chemist who discovered selenium, visit this Web site from the European Association for Chemical and Molecular Sciences: www.euchems.org /Distinguished/19thCentury/berzelius.asp * To learn about the dietary value of selenium, visit this Web site from the National Institutes of Health: http://ods.od.nih.gov/factsheets/selenium.asp * For safety information on selenium, visit this Web site from the Agency for Toxic Substances and Disease Registry The United States Agency for Toxic Substances and Disease Registry, (ATSDR) is an agency for the U.S. Department of Health and Human Services that is directed by a congressional mandate to perform specific functions concerning the effect on public health of hazardous : www.atsdr.cdc.gov/toxprofiles/phs92.html * For more information on selenium and HIV suppression, visit this Web site from the University of Miami School of Medicine: www.med.miami.edu/news/view.asp?id=720 * This Web site from the University of Delaware [3] The student body at the University of Delaware is largely an undergraduate population. Delaware students have a great deal of access to work and internship opportunities. has a slideshow that demonstrates how a photocopier works: www.physics.udel.edu/~watson/scen103/less.copier.html ANSWER HANDS-ON, p. 13 1. Answers will vary IT'S YOUR CHOICE, p. 20 1. Selenium 2. a 3. c 4. d 5. d 6. d YOU CAN DO IT, p. 22 Explain This! Last January, a worker in Riga, Latvia helped drain the city of floodwaters. The day after a huge rainstorm he removed a street's heavy manhole cover. Gravity pulled the excess rainwater underground and into a series of pipes belonging to the city's sewer system. As the floodwater flood·wa·ter n. The water of a flood. Often used in the plural. floodwater n → aguas fpl (de la inundación) floodwater n traveled through the pipes, it mixed with water drained from the city's showers, sinks, and toilets. The mixture ended up at a wastewater treatment plant Wastewater treatment plant also called wastewater treatment works
CROSSWORD [ILLUSTRATION OMITTED] BRAIN TEASER The first Tuesday in July NEW QUIZ, TE 4 1. b 2. c 3. a 4. c 5. d 6. b 7. c 8. c 9. b 10. d SAIL AWAY, TE 5 1. The boat sailed across the Atlantic Ocean Across the Atlantic Ocean is the twenty-eighth episode[1] of Mobile Suit Gundam. Plot summary Amuro and Sayla manage to reduce their time in docking the Gundam and the G-Fighter to fifteen seconds. and the Indian Ocean. 2. The boat sailed eastward between August 5 and August 31. 3. Answer will vary. |
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