Solution Manual For Earth Science, 14th Edition

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1The chapterIntroduction to Earth Scienceopens by listing and describing what sciences comprise theencompassing heading of Earth science. These include geology, oceanography, meteorology, astronomy, andenvironmental science. It goes on to introduce the concept of scales of space and time. The nature of scientificinquiry is discussed. The chapter explains the origins and creation of the Earth and solar system while notingthe differences in how the inner and outer planets formed. Earth’s four major spheres are addressed. Thesespheres are the hydrosphere, atmosphere, biosphere, and geosphere. The chapter looks at Earth’s internalstructure from both a physical properties and a chemical composition point of view. This leads to the conceptof plate tectonics and a brief introduction to plate boundary types. A quick overview of the differencebetween major continental features and major oceanic features follows. The chapter wraps up by discussinghow and why Earth is a system, citing examples of feedback loops and how people interact with the Earthsystem.FOCUS ON CONCEPTSAfter reading, studying, and discussing the chapter, students should be able to:1.1List and describe the sciences that collectively make up Earth science. Discuss the scales of space andtime in Earth science.1.2Discuss the nature of scientific inquiry and distinguish between a hypothesis and a theory.1.3Outline the stages in the formation of our solar system.1.4List and describe Earth’s four major spheres.1.5Label a diagram that shows Earth’s internal structure. Briefly explain why the geosphere can bedescribed as being mobile.1.6List and describe the major features of the continents and ocean basins.1.7Definesystemand explain why Earth is considered to be a system.STRATEGIES FOR TEACHING EARTH SCIENCEChapter 1 is meant to be an introductory chapter. Use this chapter to highlight topics in which you haveparticular expertise or that you expect to cover in more detail throughout the course. Since it is meant to be anoverview of Earth science, avoid the pitfall of going into great detail about each topic at the beginning of yourcourse when students are reading this chapter. Give students the general idea of what they will encounterduring the course. It may be useful to point out which chapters explore particular topics in more detail for thecoming weeks.•Pose the question, “What is Earth science?” Consider having students discuss this question withothers seated near them and asking for collective answers. This is also a good icebreaker for the startof a course, so that students may meet others in the class.•Have students brainstorm, either individually or in small groups, ways that Earth science affectsthem. Have them think of how they impact the Earth.•Use a visual aid to help students grasp the concept of geologic time. Construct a toilet paper geologictime scale prior to class (see Additional Resources). This generates student interest and shows theChapter1Introduction to Earth Science

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2vastness of geologic time in a concrete way. Alternatively, have students construct their owncalculator tape time scale (also in Additional Resources) for a more interactive experience.•Make a list of statements where some are hypotheses and some are theories but don’t tell the studentswhich are which. Present these to the class and have students make their own decisions about whichstatements are hypotheses and which are theories. Reveal the correct answers and discuss what makesa statement a hypothesis or a theory. Students retain the information better if they’ve tried to figure itout before you’ve actually presented it.•When discussing the origins of the solar system, stress the differences between the inner and outerplanets; the inner planets are terrestrial whereas the outer planets are gaseous.•Before introducing Earth’s spheres, have students come up with lists of features that are naturally apart of Earth. They may be surprised at the things they did not think of (or did think of) as part of thestudy of Earth science.•Save the detailed discussion of Earth’s interior structure for later when it is covered in more detail inthe book. However, it may be useful to bring a hardboiled egg and slice it in half. Use the analogythat the shell of the egg approximates the thickness of Earth’s crust, so that students see how thin alayer it is.•Introduce students to the idea that continental crust and oceanic crust are two different rock types.Ask students to describe some of the more notable features of continents and ocean basins.•Be sure to use visuals when describing introductory plate tectonics. At this stage illustrations anddiagrams from the text should suffice. Video clips and animations will be useful later.•When introducing the concept that Earth is a system, have students come up with their own ideas ofwhat constitutes a system. Relate a few of those ideas back to the Earth system, stressing theinterconnectedness of everything.Teaching Strategy Summary for Chapter 1Keep it basic and introductory. Give students a glimpse at the course ahead of them. Get students involvedin thinking about concepts rather than just presenting the ideas as slides or notes. Students will feelmore ownership over the course material if you give them opportunities to think about a topic before youlecture on it.CONCEPT CHECK ANSWERSConcept Check 1.11.List and briefly describe the sciences that collectively make up Earth science.•Geology – this is the study of the solid Earth. Physical geology examines the materials thatcomprise the Earth and historical geology aims to understand the origins and development of theplanet.•Oceanography – examines the composition and dynamics of the world’s oceans. It also involvesthe study of coastal processes and seafloor topography as well as marine life.•Meteorology – this is the study of Earth’s atmosphere. It includes weather and climate.•Astronomy – this examines Earth as a body in space, both as part of the solar system and as partof a larger universe.•Environmental science – includes the study of natural resources, environmental hazards, and howpeople influence their environments and Earth processes.

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32.Name the two broad subdivisions of geology and distinguish between them.•Physical geology – this is the study of the materials and processes that define the planet Earth. Itincludes the study of Earth’s composition, events such as volcanism, and the dynamics of Earthprocesses such as plate tectonics.•Historical geology – this is the study of the origins and evolution of Earth. It pieces together achronological history of Earth based on clues in the rock record. These clues can include evidenceof physical and biological changes throughout Earth’s 4.6 billion year history.3.List at least four different natural hazards.•Earthquakes•Volcanoes•Floods•Tsunami•Hurricanes•Landslides4.Aside from natural hazards, describe another important connection between people and Earthscience.Humans influence Earth by altering its surface. People build cities and roads, and engineer projects thatalter river flooding patterns. People pollute the air, the land, and the water, changing Earth from what isits natural state.5.List two examples of size/place scales in Earth science that are at opposite ends of the spectrum.•A lightning flash happens within a fraction of a second but can instantly alter the immediatelandscape.•Uplift of mountain ranges takes tens to hundreds of millions of years to occur.6.How old is Earth?4.6 billion years old.7.If you compress geologic time into a single year, how much time has elapsed since Columbusarrived in the New World?3 seconds.Concept Check 1.21.How is a scientific hypothesis different from a scientific theory?A hypothesis is an untested explanation for an observed phenomenon. It requires further observation ortesting to see if it is valid. A theory is generally accepted by the scientific community as the bestexplanation for observable facts, as it has been subjected to rigorous scrutiny and tested repeatedly.2.Summarize the basic steps followed in many scientific investigations.•An observation is made about the natural world.•Data surrounding that observation are collected.•A working hypothesis is developed.•More observations and/or experiments are performed to test the hypothesis.•The hypothesis is accepted, rejected, or modified.•Data and results are shared with the scientific community for critical analysis and further testing.

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4Concept Check 1.31.Name and briefly outline the theory that describes the formation of our solar system.The nebular theory states that the early solar system originated as a cloud of dust and gas about 5 billionyears ago as a star gravitationally collapsed. This rotating nebular cloud eventually contracted into aflattened, rotating disk. The cloud cooled and heavier metallic and rocky material condensed and accretedinto the inner planets. The outer planets formed from residual gases and ices in the outer nebular cloud.2.List the inner planets and the outer planets. Describe basic differences in size and composition.Inner planets: Mercury, Venus, Earth, and Mars. These planets are relatively small and rocky; they aremade up largely of metals and silicate minerals.Outer planets: Jupiter, Saturn, Uranus, and Neptune. These planets are much larger than the inner planetsand are composed of ices and gases.Concept Check 1.41.List Earth’s four spheres.•Atmosphere•Hydrosphere•Biosphere•Geosphere2.Compare the height of the atmosphere to the thickness of the geosphere.The atmosphere is a very thin layer compared to the planet itself. The radius of the solid Earth is about6400 km (4000 mi) whereas the entire atmosphere is roughly 160 km (100 mi) thick.3.How much of Earth’s surface do oceans cover? How much of the planet’s total water supply dooceans represent?Oceans cover 70% of the planet. They account for 97% of Earth’s water supply.4.To which sphere does soil belong?GeosphereConcept Check 1.51.List and briefly describe Earth’s compositional layers.•Crust – this is the outermost layer of Earth. It is very thin and made up of oceanic and continentaltypes of crust.•Mantle – this is a semi-molten, relatively thick layer of Earth. It is divided into the upper andlower mantle and its semi-fluid state allows for plate tectonics.•Core – this is at the center of Earth. The inner core is solid nickel and iron, whereas the outer coreis liquid. It is the thickest of all Earth’s structural layers.2.Contrast the lithosphere and the asthenosphere.The lithosphere is the relatively cool, hard, outer shell of Earth’s crust. The asthenosphere is relativelysoft and has some melting in its upper layer. The different natures of these two layers, which are incontact with each other, is what allows for plate tectonics, where the hard lithosphere moves on the semi-fluid upper portion of the asthenosphere.

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53.What are lithospheric plates? List the three types of boundaries that separate plates.Lithospheric plates are the broken up slabs of Earth’s rigid outer shell, the lithosphere. The three types ofplate boundaries are divergent, convergent, and transform fault.Concept Check 1.61.Contrast continents and ocean basins.Continents are made of granitic rocks whereas oceans are made of basaltic rocks. Continents are lessdense and thicker than ocean basins.2.Describe the general distribution of Earth’s youngest mountains.They are at the margins of continents.3.What is the difference between shields and stable platforms?A shield is a large stable area of very old crystalline rock. A stable platform is a shield covered bysedimentary rock.4.What are the three major regions of the ocean floor and some features associated with each region?•Continental margins – contains the continental shelf, the continental slope, and the continentalrise. It is the boundary between continents and oceans.•Deep-ocean basins – these include the vast, flat abyssal plains of the ocean bottom. They alsocontain deep ocean trenches and seamounts in varied stages of erosion.•Oceanic ridges – these are divergent plate boundaries where new igneous rock is formed. Theseare vast winding ridges of underwater volcanic mountains that wind around the Earth.Concept Check 1.71.What is a system? List three examples of systems.A system is a group of interacting, independent parts that make up a complex whole. Examples ofsystems include a city transportation system, a weather system, or an automotive cooling system.2.What are the two sources of energy for the Earth system?The Sun and Earth’s interior.3.Predict how a change in the hydrologic cycle, such as increased rainfall in an area, might influencethe biosphere and geosphere in that area.An increase in rainfall might affect the biosphere by changing the amount and types of vegetation foundin that area. In turn, the vegetation change could alter the types of animals that inhabit the region.Increasing the rainfall could affect the geosphere by increasing erosion. Conversely, if vegetationincreases also, the plants could be a stabilizing factor that decreases erosion.GIVE IT SOME THOUGHT ANSWERS1.After entering a dark room, you turn on a wall switch, but the light does not come on. Suggest atleast three hypotheses that might explain this observation. How would you determine which one ofyour hypotheses (if any) is correct?•There is a local power outage.•The light source (bulbs, tubes, etc.) is “burned out” and no longer working.•The electricity to the room is not turned on or has been disconnected.

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6You can determine which of these is correct by testing the hypothesis. For example, you can replace thelight bulb with a new one to see if it works. You can look at the circuit breakers and see if any of them arenot on. You can call the electric company to see if service has been discontinued or if there are generalpower outages in your area.2.Each of the following statements may either be a hypothesis (H), a theory (T), or an observation(O). Use one of these letters to identify each statement. Briefly explain each choice.a.A scientist proposes that a recently discovered large ring-shaped structure on the CanadianShield is the remains of an ancient meteorite crater.b.The Redwall Formation in the Grand Canyon is composed primarily of limestone.c.The outer part of Earth consists of several large plates that move and interact with each other.d.Since 1885, the terminus of Canada’s Athabasca Glacier has receded 1.5 kilometers.a.Hypothesis – it is a tentative explanationb.Observationc.Theory – well tested and widely accepted by the scientific communityd.Observation – direct measurement of how far the glacier has moved3.Makingaccuratemeasurementsandobservationsisabasicpartofscientificinquiry.Theaccompanying radar image, showing the distribution and intensity of precipitation associated witha storm, provides one example. Identify another image in this chapter that illustrates a way inwhich scientific data are gathered. Suggest an advantage that might be associated with the exampleyou select.Figure 1.7 shows a paleontologist collecting fossils. An advantage of fossil data is that it is concrete andobservable. Fossils can be used to tell about the past climate of an area and they can be used to helpdetermine the age of the rocks in which it was found, and the ages of surrounding rocks.4.The length of recorded history for humankind is about 5000 years. Clearly, most people view thisspan as being very long. How does it compare to the length of geologic time? Calculate thepercentageorfractionofgeologictimethatisrepresentedbyrecordedhistory.Tomakecalculations easier, round the age of Earth to the nearest billion.5000/5,000,000,000= 0.000001%5.Refer to the graph in Figure 1.13 to answer the following questions.a.If you were to climb to the top of Mount Everest, how many breaths of air would you have totake at that altitude to equal one breath at sea level?Air pressure at the top of Mount Everest is about 1/3 that at sea level, so you would need to take 3breaths relative to sea level.b.If you are flying in a commercial jet at an altitude of 12 kilometers (about 39,000 feet), aboutwhat percentage of the atmosphere’s mass is below you?About 75% of the atmosphere’s mass is below you.6.Examine Figure 1.12 to answer these questions.a.Where is most of Earth’s freshwater stored?Glaciersb.Where is most of Earth’s liquid freshwater found?Groundwater

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77.Jupiter, the largest planet in our solar system, is 5.2 astronomical units (AU) from the Sun. HowlongwouldittaketogofromEarthtoJupiterifyoutraveledasfastasajet(1000kilometers/hour)? Do the same calculation for Neptune, which is 30 AU from the Sun. Referring tothe GEOgraphics feature on page 15 will be helpful.1 AU = 150 million km. 5.2 AU × 150,000,000 km = 780,000,000 km780,000,000 km × hour/1000 km = 780,000 hrs = 32,500 days = 89 yearsNeptune: 30 AU × 150 million km = 4.5 billion km4.5 billion km × hour/1000 km = 4,500,000 hours = 187,500 days = 513.7 years8.These rock layers consist of materials such as sand, mud, and gravel that, over a span of millions ofyears, were deposited by rivers, waves, wind, and glaciers. Each layer was buried by subsequentdeposits and eventually compacted and cemented into solid rock. Later, the region was uplifted,and erosion exposed the layers seen here.a.Can you establish a relative time scale for these rocks? That is, can you determine which one ofthe layers shown here is likely oldest and which is probably youngest?b.Explain the logic you used.The oldest rock is on the bottom and the youngest is on the top. Each layer was put down successively;therefore newer rock kept building upon the rock already in place.EXAMINING THE EARTH SYSTEM ANSWERS1.This scene is in British Columbia’s Mount Robson Provincial Park. The park is named for thehighest peak in the Canadian Rockies.a.List as many examples as possible of features associated with each of Earth’s four spheres.Geosphere – mountains, rockBiosphere – trees, vegetation on slopesHydrosphere – lake, ice on mountain slopeAtmosphere – sky, cloudsb.Which, if any, of these features was created by internal processes? Describe the role of externalprocesses in this scene.The mountains were created by internal processes. Earth’s internal heat engine is responsible for platetectonics. Plate tectonics drives mountain building.External processes in this scene would include precipitation to create the lake and the water for theice. Erosion would generate the soil for the trees to grow in. Erosion would also shape the rockfeatures and mountains. Atmospheric temperature determines the state of matter of the water.2.Humans are a part of the Earth system. List at least three examples of how you, in particular,influence one or more of Earth’s major spheres.Answers will vary. Examples could include driving a car and putting pollution in the atmosphere, livingin a home heated by natural gas taken from the Earth, eating food that requires clearing of forests to createcropland.3.The accompanying photo provides an example of interactions among different parts of the Earthsystem.Itisaviewofadebrisflow(popularlycalledamudslide)thatwastriggeredbyextraordinary rains. Which of Earth’s four spheres were involved in this natural disaster, whichburied a small town on the Philippine island of Leyte? Describe how each contributed to or wasinfluenced by the event.Geosphere – contains the soil that became mud flowing down the mountain. The geosphere is also part ofthe topography that created the mountain.

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8Atmosphere – heavy rains fell during an atmospheric event.Biosphere – any vegetation growing on the slope or in the path of the mudslide will have been uprootedor destroyed.Hydrosphere – water that fell to the earth saturated the soil and became part of the hydrosphere. Thehydrosphere also contained the water that was evaporated and eventually became the rainfall thattriggered this event.4.Examine the accompanying concept map that links the four spheres of the Earth system. All of thespheres are linked by arrows that represent processes by which the spheres interact and influenceeach other. For each arrow list at least one process.Atmosphere – Hydrosphere – Water evaporates from the hydrosphere into the atmosphere and waterprecipitates from the atmosphere to become part of the hydrosphere.Hydrosphere – Geosphere – The geosphere creates the topography in which lakes, rivers, and oceanbasins can form.Geosphere – Biosphere – The geosphere contains the soil in which vegetation may grow.Biosphere – Atmosphere – Plants transpire moisture into the atmosphere and they respire oxygen into theatmosphere.Atmosphere – Geosphere – The atmosphere generates precipitation that can trigger erosion.Hydrosphere – Biosphere – The hydrosphere contains ground water that allows growth of vegetation.DISCUSSION TOPICS•Why study Earth science?•Do you think the scientific method is an exact recipe that scientists follow or more of a set ofguidelines for investigation? Explain your reasoning.•Why do we make a distinction between the different “spheres” of Earth?•What do Earth scientists mean when they speak of change as a constant?•Why is it important to recognize Earth as a system? When can it be more relevant to study individualparts of the system?ADDITIONAL RESOURCESDVDs or Movies•How the Earth Was Made(2008) Narrated by Alec Baldwin. History Channel, 1 hour 34 minutes•Inside Planet Earth(2008) Narrated by Patrick Stewart. Discovery Channel, 2 hours.•Earth Revealed, Episode 1: Down to Earth(1992) Annenberg Media, 30 minutes. Available on DVDor for free streaming video on demand from http://www.learner.org/resources/series78.htmlWebsites•Evolution of Our Solar System – Framework for an interactive classroom activity where studentslearntheorderofeventsthatcreatedthesolarsystem.http://www.lpi.usra.edu/education/timeline/activity/•Earth Science Picture of the Day – Various pictures that can open up discussion in the classroom.http://epod.usra.edu•Toilet Paper Geologic Time Scale – Directions for creating a visual time scale analogy for a classdemonstration.http://serc.carleton.edu/quantskills/activities/TPGeoTime.html•Calculator Tape Time Scale – Similar to the toilet paper time scale except students do the calculationsand create the time scale themselves.http://serc.carleton.edu/quantskills/activities/calculatortape.html

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9Matter and Mineralsbegins with an explanation of what defines a mineral by listing the characteristics onelooks for when determining if something is a mineral. It continues to describe what defines a rock and brieflycompares and contrasts rocks versus minerals. The chapter continues with a discussion of atoms and howelements are the building blocks of minerals. Parts of an atom are discussed and the periodic table of theelements is introduced in the context of mineralogy. Atomic bonding is examined as a lead in to discussingmineral properties. The various properties that define a mineral are presented in detail. These propertiesinclude luster, color, light transmittance, streak, crystal shape or habit, hardness, cleavage, fracture, tenacity,and specific gravity.After discussing these introductory concepts, the chapter identifies the various mineral groups, differentiatingbetween silicate and nonsilicate minerals. The most abundant elements from the periodic table are presentedas the major constituents of Earth’s crust. The structure and other properties of major silicate minerals areshown, and the names of these minerals are presented. A distinction is made between light and dark silicatesand the reasons for these color variations. Important nonsilicate minerals are then presented.There is a brief discussion of natural resources, and mineral resources are examined in this context.Economics of minerals and mineral extraction methods end this chapter.FOCUS ON CONCEPTSAfter reading, studying, and discussing the chapter, students should be able to:2.1List the main characteristics that an Earth material must possess to be considered a mineral anddescribe each.2.2Compare and contrast the three primary particles contained in atoms.2.3Distinguish among ionic bonds, covalent bonds, and metallic bonds.2.4List and describe the properties that are used in mineral identification.2.5List the common silicate and nonsilicate minerals and describe the characteristics of each group.2.6Discuss Earth’s natural resources in terms of renewability. Differentiate between mineral resourcesand ore deposits.TEACHING TIPSChapter 2 contains what, for many students, is a great deal of new information coupled with a lot ofnew vocabulary. Pace yourself and be sure any new information, such as mineral names andcharacteristics, are presented clearly. Having lots of hand samples as visual aids retains studentinterest as well as helps you to illustrate your points. Much of what there is to learn about minerals isvisual so visuals are very important for this chapter in particular.•If you discuss the periodic table, atoms, and bonding, be sure to make references to howthese topics relate to minerals. Students tend to think of these topics as being “chemistry” soChapter2Matter and Minerals

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10giving them a relationship to Earth science will keep these concepts fresh and give students adifferent perspective.•When explaining the difference between a mineral and a rock, have a large hand sample ofsomething that is clearly a mineral, e.g. feldspar, and a hand sample of a rock that clearly isan aggregate of minerals, e.g. granite. This helps illustrate how minerals can be constituentsof rocks or rocks in and of themselves.•You can simultaneously introduce the concepts of mineral cleavage and internal bonding bybringing to class a large hand sample of a readily and obviously cleaved mineral such ashalite, calcite, or feldspar. Also bring a rock hammer and safety goggles. Show how when hitwith a hammer, the mineral cleaves along consistent planes. Use this to explain how itreflects patterns of weak atomic bonding within the mineral.•Students often confuse the crystal form of quartz for cleavage, when quartz only exhibitsfracture. If you have a quartz sample to spare, you might hit it with a rock hammer todemonstrate fracture and reinforce the fact that crystal form and cleavage are two verydifferent things, but both are a reflection of internal atomic structure.•If you do not have the capacity to demonstrate fracture or cleavage in your classroom,consider using short YouTube video clips where these properties are demonstrated by others.•If your course has a laboratory component, leave the heavy duty teaching and memorizationof mineral names to the lab. In the laboratory, students will have several hours with hands-onaccess to the samples and be able to observe the minerals’ properties for themselves whileassociating them with names.•Whether or not your course has a laboratory component, consider bringing examples ofminerals to class. When illustrating different properties, select classic examples of mineralsthat show these properties. For example:oMetallic luster – galenaoStreak – chalk or hematiteoHardness – scratch glass with quartz and scratch talc with a fingernail. Challenge astudent to try to scratch glass with talc or some other soft mineral.oCrystal form – halite or quartz•When discussing the 8 most abundant elements in Earth’s crust, it can be useful to show thislist in conjunction with a Periodic Table so that students can see how very few elements areresponsible for what we know of as Earth.•Some students are already familiar with some gemstones. Framing minerals in the context ofgems that they may know can be useful for some.•Before you talk about natural resources, have students in groups or individually look aroundthem and try to determine what things in the room or building might have been extractedfrom the Earth. Quartz clocks and watches, silicon in computers, and metals used to constructvarious items are a few of the things they may come up with.Teaching Strategy Summary for Chapter 2Use lots of visual aids. Either engage students in hands-on interaction with minerals or preparedemonstrations of the various qualities associated with minerals.

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11CONCEPT CHECK ANSWERSConcept Check 2.11.List two characteristics an Earth material must have in order to be considered a mineral.•Naturally occurring•Generally inorganic•Solid•Orderly crystalline structure•Definite chemical composition.2.Define the termrock.How do rocks differ from minerals?Rocks are more loosely defined as aggregates of different minerals. Rocks differ from minerals because theymay be of varied mineral content and they may contain nonmineral matter.Concept Check 2.21.List the three main particles of an atom and explain how they differ from one another.•Proton – positively charged particle in the nucleus of the atom. The number of protons is the sameas the element number.•Neutron – particle in the nucleus of the atom. It has no charge associated with it.•Electron – negatively charged particle that orbits the nucleus. There are the same number ofelectrons as protons in a given element.2.Make a simple sketch of an atom and label its three main particles.See Figure 2.4.3.What is the significance of valence electrons?The valence shell of an atom is its outermost shell and responsible for bonding with other atoms. Theelectrons of the valence shell are those that are shared with other atoms in the bonding process.Concept Check 2.31.What is the difference between an atom and an ion?An atom does not have a charge because it has an equal number of protons or electrons. Ions have eithergiven up or taken on more electrons, giving the ion a positive or negative charge.2.What occurs in an atom to produce a positive ion? A negative ion?An atom that has given up one or more valence electrons becomes a positive ion. An atom that has takenon extra valence electrons becomes a negative ion.3.Briefly distinguish among ionic, covalent, and metallic bonding and describe the role that electronsplay in each.•Ionic bonding – one atom “donates” its electrons to another, creating two ions bonded to eachother.•Covalent bonding – two atoms equally share valence electrons.•Metallic bonding – several atoms contribute their valence electrons to a pool of electrons that arefree to move through the entire structure.

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12Concept Check 2.41.Defineluster.Luster describes the quality of light reflected from a mineral’s surface. It may be metallic or nonmetallic,with several subdistinctions among nonmetallic lusters.2.Why is color not always a useful property in mineral identification? Give an example of a mineralthat supports your answer.There may be small impurities in the mineral that will alter its color. Quartz is a notable example, withrose quartz (pink) and amethyst (purple) being only two examples of color variants.3.What differentiates cleavage from fracture?Cleavage occurs when a mineral breaks cleanly along a plane. This is due to a plane of weak atomicbonding within the mineral. Fracture occurs when there is no distinct plane along which the mineral canbreak; when hit with a rock hammer, the mineral will fracture into irregular pieces.4.What do we mean when we refer to a mineral’s tenacity? List three terms that describe tenacity.Tenacity is a mineral’s resistance to cutting, breaking, and other forms of deformation. Three terms thatdescribe tenacity arebrittle, malleable,andsectile. Elasticis another term.5.What simple chemical test is useful in the identification of the mineral calcite?Putting a drop of weak acid, such as HCl, on the mineral will create a visible reaction with bubbling onthe surface.Concept Check 2.51.List the eight most common elements in Earth’s crust, in order of abundance (most to least).Oxygen, silicon, aluminum, iron, calcium, sodium, potassium, magnesium.2.Explain the difference betweensiliconandsilicate.Silicon is an element. Silicates contain silicon and oxygen and are the major constituents of continentalcrust.3.Draw a sketch of the silicon-oxygen tetrahedron.See Figure 2.23.4.What is the most abundant mineral in Earth’s crust?Feldspar5.List six common nonsilicate mineral groups. What key ion(s) or element(s) define each group?•Carbonates – CO3ion•Halides – F, Cl, Br•Oxides – O•Sulfides – S•Sulfates – SO4ion•Native elements – various single elements such as gold and copper.6.What is the most common carbonate mineral?Calcite7.List eight common nonsilicate minerals and their economic uses.•Calcite – Portland cement, lime•Halite – salt

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13•Fluorite – steelmaking•Hematite – Ore of iron•Galena – Ore of lead•Sphalerite – Ore of zinc•Chalcopyrite – Ore of copper•Silver – JewelryConcept Check 2.61.List three examples of renewable resources and three examples of nonrenewable resources.•Renewable – solar, forests and trees, water•Nonrenewable – Metals, oil, coal2.Compare and contrast a mineral resource and an ore deposit.Mineral resources are occurrences of useful minerals in such large amounts that extraction is reasonablycertain. An ore deposit is a naturally occurring concentration of one or more minerals with economicvalue. Mineral resources include deposits that are not economically viable to recover where ore depositsare.3.Explain how a mineral deposit that previously could not be mined profitably might be upgraded toan ore deposit.Demand for a metal may increase its value or technological advances may make it more profitable toextract the metal than previously.GIVE IT SOME THOUGHT ANSWERS1.Using the geologic definition ofmineralas your guide, determine which of the items in this list areminerals and which are not. If something in this list is not a mineral, explain.a. mineral – gold is an example of a mineral classified as a native element; b. seawater is not a mineral –minerals by definition are solids; c. quartz is a mineral; d. cubic zirconia is not a mineral – it is notnaturally occurring; e. obsidian is not a mineral because it lacks an internal arrangement of atoms,however, it is an igneous rock; f. ruby is a mineral – it is a gemstone variety of the mineral corundum; g.glacial ice is a mineral as it meets all of the criteria; h. amber is not a mineral since it has an organicorigin.2.Assume that the number of protons in a neutral atom is 92 and its mass number is 238.a.What is the element?b.How many electrons does it have?c.How many neutrons does it have?a. The element is uranium.b. 92 electronsc. 146 neutrons3.Which of the following elements is more likely to form chemical bonds: xenon (Xe) or sodium (Na)?Explain why.Sodium is more likely to form chemical bonds because of its tendency to lose one electron, resulting in anoverall +1 charge.4.Referring to the accompanying photos of five minerals, determine which of these specimens exhibita metallic luster and which have a nonmetallic luster.Specimens A, B, and D have a nonmetallic luster. Specimens C and E have a metallic luster.

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145.Gold has a specific gravity of almost 20. A 5-gallon bucket of water weighs 40 pounds. How muchwould a 5-gallon bucket of gold weigh?5 gallons of water = 40 lbs. × 20 (specific gravity of gold) = 800 lbs.6.Examine the accompanying photo of a mineral that has several smooth, flat surfaces that resultedwhen the specimen was broken.a.How many flat surfaces are present on this specimen?b.How many different directions of cleavage does this specimen have?c.Do the cleavage directions meet at 90-degree angles?a. 6b. 3c. no7.Each of the following statements describes a silicate mineral or mineral group. In each case,provide the appropriate name.a.The most common member of the amphibole groupb.The most common light-colored member of the mica familyc.The only common silicate mineral made entirely of silicon and oxygend.A silicate mineral with a name that is based on its colore.A silicate mineral that is characterized by striationsf.A silicate mineral that originates as a product of chemical weatheringa. Hornblendeb. Muscovitec. Quartzd. Rose quartze. Feldsparf. Calcite8.What mineral property is illustrated in the accompanying photo?Cleavage.9.Do an Internet search to determine what minerals are extracted from the ground during themanufacture of the following products.a.Stainless steel utensilsb.Cat litterc.Tums brand antacid tabletsd.Lithium batteriese.Aluminum beverage cansAnswers may vary slightly depending on which websites are utilized by students.10. Most states have designated a state mineral, rock, or gemstone to promote interest in the state’snatural resources. Describe your state mineral, rock, or gemstone and explain why it was selected.If your state does not have a state mineral, rock, or gemstone, complete the exercise by selecting onefrom a state adjacent to yours.Answers will vary.DISCUSSION TOPICS•What are some renewable and nonrenewable resources you use regularly?•How many of the elements of the Periodic Table have you used or encountered? How many of thoseelements are one of the 8 major constituents of Earth’s crust?•Why do you think a mineral has to be non-organic?•Why do you think a mineral has to be naturally occurring to be classified as a mineral?•What are some minerals you use regularly?

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15ADDITIONAL RESOURCESDVDs or Movies•Rocking Around the Silicates,Performed by Richard Alley, Penn State University, 4 minutes, 23seconds. http://www.youtube.com/watch?v=utypgC7h6f4•Earth Revealed, Episode 12: Minerals: The Materials of Earth(1992) Annenberg Media, 30 minutes.Available on DVD or for free streaming video on demand from http://www.learner.org/resources/series78.htmlWebsites•Name that Atom Interactive Game. http://www.learner.org/interactives/periodic/basics_interactive.html•Online Mineral Identification – Contains pictures of minerals. Students decide which properties to“test”toidentifythemineral.http://facweb.bhc.edu/academics/science/harwoodr/geol101/labs/minerals/•Mineral Identification Key – From the Mineralogical Society of America. Takes the student step bystep through the identification process for a sample that the student has in his/her possession.http://www.minsocam.org/msa/collectors_corner/id/mineral_id_keyq1.htm•Online Mineral Museum – Comprehensive listing of minerals with pictures, chemical formulas, andwhere they are commonly found. http://www.johnbetts-fineminerals.com/museum.htm•The Dynamic Earth from the Smithsonian Institution’s National Museum of Natural History –Choose “Gems and Minerals” Interactive exhibit where students can learn about mineral growth andformation, and about gemstones. Highlights specimens found at the museum in Washington, D.C. butalso a good stand-alone website for learning. http://www.mnh.si.edu/earth/main_frames.html

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