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Introduction to Chemistry7 1.1FOCUSObjectives1.1.1Identify ve traditional areas ofstudy in chemistry.1.1.2Relate pure chemistry toapplied chemistry.1.1.3Identify reasons to studychemistry. Guide for ReadingGuide for ReadingBuild VocabularyParaphrase Help students translatethe denition of technology into theirown words. For example, means mightbe a way that something gets doneasin means to an end.Reading StrategySummarize Have students write asummary of this section and thencheck the summaries to see if the sum-maries answer the key concepts ques-tions on p. 7.INSTRUCT Have students study the photographand read the text that opens the sec-tion. Ask, Why would large amountsof sulfur and sulfur dioxide be a signthat the volcanoes on Ios surface areactive?(These chemicals are usuallyreleased when volcanoes erupt onEarth.) On September 21, 2003 Galileosmission ended when its supply of pro-pellant was almost depleted.Withoutpropellent, Galileo couldnt point itsantenna toward Earth or avoid acollision with Jupiters moon Europa.Scientists programmed Galileo to col-lide with and disintegrate in Jupitersatmosphere.What Is Chemistry?DiscussDiscussTo nd out if students understand thescope of the category matter , ask themto classify items as matter or non-matter. 11L2L222L2Section ResourcesPrintGuided Reading and Study Workbook,Section 1.1Core Teaching Resources, Section 1.1Review, Interpreting GraphicsTransparencies, T1T2TechnologyInteractive Textbook with ChemASAP,Assessment 1.1Go Online, Section 1.1 Connecting to Your WorldConnecting to Your WorldConnecting to Your World Section 1.1 Chemistry7 7 1.1ChemistryChemistryThe Galileo spacecraft wasplaced in orbit around Jupiter to collect data about the planet and itsmoons. Instruments aboard Galileo analyzed the atmosphere of themoon Io.They found large amounts of sulfur andsulfur dioxide. These chemicals are usuallyreleased when volcanoes erupt on Earth.So the presence of these chemicalsveried that the volcanoes on Iossurface are active. Chemistry helpedscientists to study the geology ofa distant object in the solar system.In this section, you will learn aboutchemistry in general and ways you canuse your knowledge of chemistry. Guide for ReadingGuide for ReadingKey ConceptsWhy is the scope of chemistryso vast?What are ve traditional areasof study in chemistry?How are pure and appliedchemistry related?What are three general reasonsto study chemistry?Vocabularymatterchemistryorganic chemistryinorganic chemistrybiochemistryanalytical chemistryphysical chemistrypure chemistryapplied chemistrytechnologyReading StrategyRelating Text and Visuals Asyou read,look closely at Figure 1.2.Explain how this illustration helpsyou to understand the traditionalareas of study in chemistry.What Is Chemistry?In autumn thousands of visitors travel to New England to view vivid colorslike those in Figure 1.1. These colors appear as the trees approach the win-ter months when growth no longer takes place. The bright pigments areproduced by a complex chemical process, which depends on changes intemperature and hours of daylight. The color pigments in leaves are anexample of matter. Matter is the general term for all the things that can bedescribed as materials, or stuff.Matteris anything that has mass andoccupies space. You don't have to be able to see something for it to qualifyas matter. The air you breathe is an example of invisible matter.Chemistryis the study of the composition of matter and the changesthat matter undergoes.Because living and nonliving things are madeof matter, chemistry affects all aspects of life and most natural events.Chemistry can explain how some creatures survive deep in the oceanwhere there is no light, or why some foods taste sweet and some taste bitter.It can even explain why there are different shampoos for dry or oily hair. Figure 1.1 Chemical changesthat occur in leaves can causebrilliant displays of color. chem_TE_ch01_FPL.fm Page 7 Tuesday, August 3, 2004 9:21 AM 8Chapter 1Section 1.1 (continued)Areas of StudyDiscussAsk students to consider their activitiesduring a single day. Ask them to giveexamples of things they do thatinvolve chemical processes or contactwith chemicals.Then, ask if they canthink of four items or activities that donot in some way involve chemistry. (Itwill be hard to nd any that do not! Stu-dents could consider what they eat, whatthey wear, the products they use for per-sonal hygiene, their normal mode oftransportation, and their residence.FYIThe area that is most difcult todescribe at the start of a chemistrycourse is physical chemistry, which ishighly theoretical. Physical chemistsinvestigate the underlying scienticprinciples behind the changes thatoccur in matter. A physical chemistrycourse includes topics such as quan-tum mechanics, thermodynamics,kinetic molecular theory, and reactionmechanisms.Address MisconceptionsBased on how the term chemical isused in the media (and how it isdened in most dictionaries), studentsmay assume that the term chemicalrefers exclusively to harmful materials.Explain that chemical describes alltypes of matter, including life-sustaining substances, such aswater and oxygen. L2Gifted and TalentedChallenge students to conduct research onthe traditional areas of study in chemistry.Encourage students to set up an interviewwith a chemist at a nearby college or localresearch laboratory.They could also search forinformation online.Ask students to share theirresearch with the class. L3 Differentiated Instruction 8Chapter 1 Areas of StudyBecause the scope of chemistry is vast, chemists tend to focus on one area.Five traditional areas of study are organic chemistry, inorganicchemistry, biochemistry, analytical chemistry, and physical chemistry.Most of the chemicals found in organisms contain carbon. Organicchemistry was originally defined as the study of these carbon-based chem-icals. Today, with a few exceptions,organic chemistryis defined as thestudy of all chemicals containing carbon. By contrast,inorganic chemistryis the study of chemicals that, in general, do not contain carbon. Inorganicchemicals are found mainly in non-living things, such as rocks. The studyof processes that take place in organisms isbiochemistry.These processesinclude muscle contraction and digestion.Analytical chemistryis the areaof study that focuses on the composition of matter. A task that would fallinto this area of chemistry is measuring the level of lead in drinking water.Physical chemistryis the area that deals with the mechanism, the rate, andthe energy transfer that occurs when matter undergoes a change.The boundaries between the five areas are not firm. A chemist is likelyto be working in more than one area of chemistry at any given time. Forexample, an organic chemist uses analytical chemistry to determine thecomposition of an organic chemical. Figure 1.2 shows how research inthese areas of study can be used to keep humans healthy. Figure 1.2 Chemists studystructures and processes in thehuman body. Inferring Doesa bone contain mainly organicor inorganic chemicals?Organic ChemistryAthletes inhale chemicalsdeveloped by organicchemists to controlsymptoms of asthma.Inorganic ChemistryAn inorganic chemist mightexplain how a lack ofcalcium can affect thegrowth and repair of bones.Analytical ChemistryAnalytical chemists develop teststo detect chemicals in the blood.The tests help to show if organs inthe body are working properly. BiochemistryA biochemist might study how theenergy used for the contraction ofmuscles is produced and stored.Physical ChemistryA physical chemistmight study factorsthat affect breathingrates during exercise. chem_TE_ch01.fm Page 8 Wednesday, April 20, 2005 6:55 AM Introduction to Chemistry9 Pure and AppliedChemistryUse VisualsUse VisualsFigure 1.3 Have students study thephotographs. Ask, What is the con-nection between the photographs?(The backpack is made of nylon, which isthe material in the beaker.) Then pointout that the study of the underlyingstructure of bers was an example ofpure chemistry, which led to an exam-ple of applied chemistrythe com-mercial production of nylon. (Nylon isdiscussed as an example of a conden-sation polymer in Section 23.4.There isa demo for making nylon on p. 751.)RelateRelateThe publics perception and expecta-tions of science have changed dramati-cally over the last two hundred years.Advances in technology can lead toincreased public concern about therole that science plays in shaping thefuture.These societal concerns arereected in the work of 19th- and 20th-century novelists such as H. G.Wells,Edward Bellamy, Jules Verne, GeorgeOrwell, and Mary Shelley.Have studentsselect a novel by one of these novelistsand critically examine it to determinehow the author addressed the role ofscience, technology, and society in hisor her era. Download a worksheet on AppliedChemistry for students to com-plete, and nd additional teachersupport from NSTA SciLinks. L1L2Answers to...Figure 1.2 Students should inferthat a bone contains mainly inor-ganic materials. CheckpointSilkAspirinIn the late 1940s, Dr. Lawrence Cravenobserved that gum containing aspirin, whichwas used to relieve pain after the removal oftonsils, caused excessive bleeding in children.He hypothesized that aspirin prevented theblood from clotting.He then began to pre-scribe aspirin to prevent heart attacks.In 1985, the FDA approved aspirin forpatients who had suffered a heart attack. In1996, the FDA proposed using aspirin duringa suspected attack. In 1997, an advisory com-mittee recommended daily low doses ofaspirin for people at high risk of a heartattack. Section 1.1 Chemistry9 Pure and Applied ChemistrySome chemists enjoy doing research on fundamental aspects of chemistry.This type of research is sometimes called pure chemistry.Pure chemistryisthe pursuit of chemical knowledge for its own sake. The chemist doesntexpect that there will be any immediate practical use for the knowledge.Most chemists do research that is designed to answer a specic question.Applied chemistryis research that is directed toward a practical goal orapplication. In practice, pure chemistry and applied chemistry are oftenlinked.Pure research can lead directly to an application, but anapplication can exist before research is done to explain how it works.Nylonand aspirin provide examples of these two approaches.NylonNylonFor years, chemists didnt fully understand the structure of materi-als such as cotton and silk. Hermann Staudinger, a German chemist,proposed that these materials contained small unitsjoined together like links in a chain. In the early1930s, Wallace Carothers did experiments to testStaudingers proposal. His results supported theproposal. During his research Carothers pro-duced some materials that dont exist in nature.One of these materials, nylon, can be drawninto long, thin, silk-like bers, as shown inFigure 1.3. Because the supply of natural silk waslimited, a team of scientists and engineers wereeager to apply Carothers research to the commercialproduction of nylon. By 1939, they had perfected a large-scale method for making nylon bers.AspirinAspirinLong before researchers gured out how aspirin works, peopleused it to relieve pain. By 1950, some doctors began to recommend a lowdaily dose of aspirin for patients who were at risk for a heart attack. Manyheart attacks occur when blood clots block the ow of blood through arter-ies in the heart. Some researchers suspected that aspirin could keep bloodclots from forming. In 1971, it was discovered that aspirin can block theproduction of a group of chemicals that cause pain. These same chemicalsare also involved in the formation of blood clots.TechnologyTechnologyThe development of nylon and the use of aspirin to preventheart attacks belong to a system of applied science called technology.Technologyis the means by which a society provides its members withthose things needed and desired. Technology allows humans to do somethings more quickly or with less effort. It allows people to do things thatwould be impossible without technology, such as traveling to the moon. Inany technology, scientic knowledge is used in ways that can benet orharm people and the environment. Debates about how to use scienticknowledge are usually debates about the risks and benets of technology. CheckpointWhich material found in nature does nylon resemble? Figure 1.3 Long, thin nylonfibers are woven into the fabricused in this backpack. Otherobjects that can be made fromnylon are jackets, fishing lines,toothbrush bristles, and ropes.For: Links on AppliedChemistryVisit: www.SciLinks.orgWeb Code: cdn-1011 Facts and Figures chem_TE_ch01_FPL.fm Page 9 Tuesday, August 3, 2004 9:21 AM 10Chapter 1Section 1.1 (continued)Why Study Chemistry?TEACHERDemoTEACHERDemoExplaining the Natural WorldPurpose Students see that chemistryis involved in many natural processes.Materials slides showing events orstructures such as a volcanic eruption,a forest re, a limestone cave, a ood,lightning, a plowed eld, a reworksdisplay, someone skateboarding, pizzabeing removed from an oven, some-one pumping gasolineAdvance Prep Collect a set of slidesthat show a wide variety of events orstructures. Pick slides for which youcan make a connection to chemistrywithout having to supply details thatstudents will study later.Public librariesand visitor-information bureaus oftenhave slides that can be borrowed.Procedure Run through the set ofslides once without discussion. Discussthe common thread among theimages.Then go through the slides asecond time and explain the connec-tion to chemistry.RelateAsk students to volunteer to talk aboutcareers they are considering. Haveeach volunteer briey describe whatkinds of activities are involved in eachcareer. Challenge the class to think ofways that knowledge of chemistrywould be helpful for each career. L1L2 10Chapter 1 Why Study Chemistry?Should you use hot water or cold water to remove sunblock from a shirt?How could studying chemistry help you to be a better nurse, reghter,reporter, or chef? If your local government wanted to build a solid wasteincinerator in your town, what questions would you ask about the project?Chemistry can have an impact on all aspects of your life.Chemistrycan be useful in explaining the natural world, preparing people forcareer opportunities, and producing informed citizens.Explaining the Natural WorldYou were born with a curiosity aboutyour world. Chemistry can help you satisfy your natural desire to under-stand how things work. For example, chemistry can be seen in all aspects offood preparation. Chemistry can explain why peeled apples turn brownupon exposure to air. It can explain why the texture of eggs changes fromrunny to rm as eggs are boiled or scrambled. Chemistry can explain whywater expands as it freezes, sugar dissolves faster in hot water, and addingyeast to bread dough makes the dough rise. After you study this textbook,you will know the answers to these questions and many more.Preparing For a CareerBeing a chemist can be rewarding. Section 1.2will present some examples of how chemists contribute to society. In thisbook, you will nd features on careers that require knowledge of chemistry.Some of the choices may surprise you. You do not need to have the wordchemistin your job title to benet from knowing chemistry. For example, areghter must know which chemicals to use to ght different types ofres. A reporter may be asked to interview a chemist to gather backgroundfor a story. Turf managers are admired for the patterns they produce on aball eld while mowing grass, but their more important task is keeping thegrass healthy, which requires an understanding of soil chemistry. A photo-grapher, like the one in Figure 1.4, uses chemical processes to control thedevelopment of photographs in a darkroom. Figure 1.4 Even after theinvention of the digital camera,many photographers still workwith film. They use chemicalprocesses to develop film andproduce prints in a darkroom.Inferring Why isn't lmdeveloped under naturallight conditions? chem_TE_ch01.fm Page 10 Wednesday, April 19, 2006 5:52 PM Introduction to Chemistry11 CLASSActivityActivity CLASS Chemistry in the NewsHave students scan local and nationalnewspapers for current news storiesrelated to chemistry. Ask students tocut out one article and prepare a shortpresentation on the content of thearticle and how it relates to chemistry.ASSESSEvaluate UnderstandingEvaluate UnderstandingTo determine students understandingabout the eld of chemistry, ask, Inyour own words, how would youdene chemistry?(Chemistry is thestudy of the composition of matter andthe changes it undergoes.) What dochemists do?(Chemists study the com-position and behavior of matter.)ReteachReteachPoint out that learning about the princi-ples of chemistry will enable students tobetter understand the modern world.Ask students what is essential in theirlives, and make a short list on the board.Have students think of one or twoexamples of how chemistry plays a partin each essential product or activity. Students answers will vary, butshould reveal an understanding ofthe denition of technology. withChemASAPIf your class subscribes to theInteractive Textbook, use it toreview key concepts in Section 1.1. L233L2L1Answers To . . .Figure 1.4 Students may infer thatnatural light causes unwantedchanges to the lm.Section 1.1 Assessment1.Living and nonliving things are made ofmatter,and chemistry is the study of matter.2.organic chemistry, analytical chemistry,biochemistry, physical chemistry, andinorganic chemistry3.Pure research can lead directly to an appli-cation; an application can exist beforeresearch is done to explain how it works.4.explaining the natural world, preparingpeople for career opportunities, andproducing informed citizens5.a and c6.No, a biochemist studies processes thattake place in organisms.7.A possible answer is that knowledge ofchemistry helps a citizen evaluate dataand arrive at an informed opinion about apublic issue that involves technology. Section 1.1 Chemistry11Figure 1.5 By registering to vote,these citizens in Chicago, Illinois,can have a say in the decisionsmade by their government. Thosedecisions include how much moneyto provide for scientific research. withChemASAP Being an Informed CitizenBeing an Informed CitizenIndustry, private foundations,and the federal government all provide funds for scienticresearch. The availability of funding can inuence the directionof research. Those who distribute funds have to balance theimportance of a goal against the cost. Because there is a limit tothe money available, areas of research often compete for funds.For example, space exploration research could not takeplace without federal funding. Critics argue that the moneyspent on space exploration would be better spent on programssuch as cancer research. Those who support space explorationpoint out that NASA research has led to the development ofmany items used on Earth. These include smoke detectors,scratch-resistant plastic lenses, heart monitors, and flat-screentelevisions. What if all the money spent on space explorationwas used to find a cure for cancer? Are there enough valid ave-nues of research to take advantage of the extra funding? Wouldthere be qualified scientists to do the research?Like the citizens shown in Figure 1.5, you will need to makechoices that will influence the development of technology. Youmay vote directly on some issues through ballot initiatives orindirectly through the officials you elect. You may speak at apublic hearing or write a letter to the editor or sign a petition.When it comes to technology, there is no one correct answer.But knowledge of chemistry and other sciences can help youevaluate the data presented, arrive at an informed opinion, andtake appropriate action.1.Key ConceptExplain why chemistry affects allaspects of life and most natural events.2.Key ConceptName the ve traditional areasinto which chemistry can be divided.3.Key ConceptDescribe the relationshipbetween pure chemistry and applied chemistry.4.Key ConceptList three reasons forstudying chemistry.5.Workers digging a tunnel through a city nd someancient pots decorated with geometric designs.Which of the following tasks might they ask achemist to do? Explain your answer.a.Determine the materials used to make the pots.b.Explain what the designs on the pots represent.c.Recommend how to store the pots to preventfurther damage.6.Would a geologist ask a biochemist to help identifythe minerals in a rock? Explain your answer.7.Explain how knowledge of chemistry can helpyou be a more informed citizen.Describing Technology Pick one activity thatyou can do faster or with less effort because oftechnology. Write a paragraph in which you des-cribe the activity, identify the technology, andexplain how the technology affects the activity.Assessment 1.1 Test yourselfon the concepts in Section 1.1. 1.1Section Assessment chem_TE_ch01_FPL.fm Page 11 Tuesday, August 3, 2004 9:21 AM