Carbon: The Element of Life from the six-part. Elements of Chemistry Series

Transcription

1 Carbon: The Element of Life from the six-part Elements of Chemistry Series Produced by Algonquin Educational Productions Distributed by FAX

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3 Table of Contents Introduction Links to Curriculum Standards Student Objectives Summary of the Program Pre-Test and Post-Test Teacher Preparation Student Preparation Description of Blackline Masters Answer Key Discussion Questions Follow-Up Activities References Script of Narration This video is closed captioned. The purchase of this program entitles the user to the right to reproduce or duplicate, in whole or in part, this teacher s guide and the blackline master handouts that accompany it for the purpose of teaching in conjunction with this program, Carbon: The Element of Life. This right is restricted only for use with this program. Any reproduction or duplication in whole or in part of this guide and the blackline master handouts for any purpose other than for use with this program is prohibited.

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5 Carbon: The Element of Life from the six-part Elements of Chemistry Series Grades 9 to 12 Viewing Time: 20 minutes INTRODUCTION Carbon: The Element of Life is part of the Elements of Chemistry Series, a six-part series of programs to help students understand the fundamental concepts of chemistry. The attractive images and engaging narration of the program have been designed by educators and filmmakers to help students understand the sometimes-complicated explanations and theories of this important branch of science. Carbon has been called "the element of life" because it is the basis of all organic substances. Carbon's ability to combine with other carbon atoms and other elements allows it to produce a vast array of chemical structures. This program explores the unique qualities of carbon and illustrates how it provides the framework for an enormous variety of organic compounds. The program provides a comprehensive introduction to this fascinating area of chemistry appropriate for high school students. LINKS TO CURRICULUM STANDARDS The Elements of Chemistry Series is based on the "National Science Educational Standards" for "Physical Science," grades 9-12, (Content Standard B). STUDENT OBJECTIVES After viewing the program and participating in the various follow up activities, students should be able to: Explain how chemists define organic matter. Explain why chemists describe organic chemistry as the study of carbon compounds. Explain the unique characteristics of carbon, which give it the ability to form a vast array of chemical substances. 1

6 Describe how the carbon atom can form short, strong, stable covalent bonds. Define hydrocarbons and give some examples. Define the characteristics of the alkane and cycloalkane families of hydrocarbons and give their general formulas. Explain unsaturated hydrocarbons and hydrocarbon derivatives. Define the alkene and alkyne family of hydrocarbons and give their general formulas. Define the rules for naming hydrocarbons. Explain what is meant by the term hydrocarbon derivatives. Give some examples of functional groups such as halocarbons and the hydroxyl group. Explain how organic polymers are compounds with a backbone of long chains of carbon atoms. Give a general description of how chemists have been able to find ways to form synthetic polymers and make a vast array of plastics. Describe in a general way that all life processes involve complex chemical reactions. Explain photosynthesis and the importance of this process for life on the planet. SUMMARY OF THE PROGRAM The element carbon is the basis of all organic substances and organic chemistry is sometimes defined as the study of carbon compounds. 2

7 Carbon's ability to combine with other carbon atoms and other elements allows it to produce a vast array of chemical substances. The secret of this unusual element lies in its atomic structure. Carbon's atomic number is 6. It is a small atom with four electrons in its outer valence level, and it needs four more electrons to fill its valence level. It usually does this by making four covalent bonds with other atoms. Carbon's small size also allows it to make short, strong, stable covalent bonds. The simplest of the carbon covalent bonds are hydrocarbons, molecules that only contain carbon and hydrogen atoms. There are thousands of different hydrocarbons. The alkane family of hydrocarbons contains only single bonds between the carbon atoms. Carbon's versatility allows it to make chains of atoms. They can also form rings. A cycloalkane is a hydrocarbon formed in a ring with single bonds between the carbon atoms. Unsaturated hydrocarbons contain double or triple bonds between a pair of carbon atoms. Alkene is the name used for compounds with double bonds, and the alkyne family has triple bonds. The naming of hydrocarbons is designed to indicate the chemical structure of the substances. There is a regular pattern to these names. The prefix indicates the number of carbon atoms and the suffix indicates the type of bond. Hydrocarbon derivatives are organic compounds containing carbon, hydrogen, and other elements. They are grouped into functional groups based on their molecular structure. Halocarbons are substances with atoms from the halogen family. The hydroxyl group containing OH, are the alcohols. There are many other groups of compounds in the functional groups. Organic polymers are made up of sub-units called monomers, which link together into long chains to make larger molecules. These polymers provide the structural strength in the stems and trunks of plants. Chemists have found ways to create synthetic polymers called plastics. 3

8 All living things are constantly involved in complex chemical reactions. Respiration, digestion, and reproduction, for example, are all chemical processes. One of the most basic life processes is photosynthesis, in which plants and some microorganisms convert carbon dioxide and water into oxygen, O2, and a form of chemical energy PRE-TEST and POST-TEST Blackline Master #1, Pre-Test, is an assessment tool intended to gauge student comprehension prior to viewing the program. Remind your students that these are key concepts upon which they should focus while watching the program. Blackline Master #7, Post-Test, can be compared to the results of the Pre-Test to determine the changes in student comprehension after participation in the activities and viewing the program TEACHER PREPARATION Before presenting this program to your students, we suggest that you preview the program and review this guide and accompanying Blackline Master activities in order to familiarize yourself with the content. Feel free to duplicate any of the Blackline Masters and distribute them to your students. As you review the materials presented in this guide, you may find it necessary to make some changes, additions, or deletions to meet the specific needs of your class. We encourage you to do this. Only by tailoring this program to your class will your students obtain the maximum instructional benefits afforded by the materials. We suggest that you first show the program in its entirety to your students. This is an introduction to an important subject of modern chemistry, and at this stage it is helpful that students gain an overview of the concepts and material in the program. A number of lesson activities will grow out of the content of the program and, therefore, the presentation should be a common experience for all students. 4

9 After the introduction the program is divided into chapters with the following titles: Carbon: The Element of Life Hydrocarbons Functional Groups Polymers and Plastics Life Processes These chapters vary in length from three to six minutes. After the students have seen the entire program, lessons could be designed around these different chapters. A chapter could be shown at the beginning of the class, and the balance of the class time, and subsequent classes, could be spent examining the subject matter in the program in greater depth. STUDENT PREPARATION It is important that students work through the material and familiarize themselves with the vocabulary, concepts, and theories that scientists use to understand this field. If the students have a textbook that they are following, assign the relevant reading before the lesson. As students work through the material, they will encounter a number of unfamiliar words and concepts. Most of these words are highlighted in the program. An additional list of words is provided in Blackline Masters #2a-c, Vocabulary Definitions and Activities. The program concludes with a ten-question Video Quiz that may be used to gauge students' comprehension immediately after the presentation of the program. Blackline Master #6, Video Quiz, is a printed copy of the questions, which may be reproduced and distributed to the students. The answers to the questions appear in the answer key of this Teacher's Guide. 5

10 DESCRIPTION OF BLACKLINE MASTERS Blackline Master #1, Pre-Test, should be given to students before viewing the program. When these answers are compared to the quiz results, it will help you gauge students' progress. Blackline Master #2a, Vocabulary Definitions, will introduce students to unfamiliar words and concepts used in this program. Blackline Master #2b, Use the Right Word, and Blackline Master #2c, Word Match, are activities designed to help reinforce key concepts and vocabulary. Blackline Master #3, Connected and Not Connected, will help students identify their knowledge of key vocabulary terms and the context in which they are used. Blackline Master #4, Crossword Puzzle, reinforces key concepts and vocabulary. Blackline Master #5, Creative Writing Story Ideas, will allow students to think creatively while incorporating scientific principles and vocabulary covered in this program. Blackline Master #6, Video Quiz, is a printed version of the Video Quiz that appears at the end of the program. Blackline Master #7, Post-Test, may be used to evaluate student progress after completing this unit of study. ANSWER KEY Blackline Master #1, Pre-Test 1. True 6. True 2. False 7. True 3. True 8. False 4. False 9. False 5. False 10. True 6

11 Blackline Master #2b, Use the Right Word 1. organic 6. hydroxyl 2. carbon 7. fossil 3. hydrocarbon 8. monomers 4. alkanes 9. reactions 5. halocarbons 10. photosynthesis Blackline Master #2c, Word Match alkenes- carbon atoms linked with a double bond alkynes- biodegrade- carbon atoms linked with a triple bond decompose carbon- element with atomic number of 6 hydrocarbon- molecules containing carbon and hydrogen hydrogen- element with atomic number of 1 hydroxylmethanemonomersplastics- group containing alcohols simplest hydrocarbon, CH4 can link into long chains synthetic polymers Blackline Master #3, Connected/Not Connected 1. organic living things 2. alkanes alkenes 3. carbon hydrogen 4. methane ethane 5. octane octyne 6. propane propyne 7. methanol ethanol 8. halocarbon hydroxyl 9. polymers monomers 10. plastics biodegradable 7

12 Blackline Master #4, Crossword Puzzle 1 2 Blackline Master #6, Video Quiz 1. True 6. False 2. True 7. True 3. False 8. False 4. True 9. True 5. False 10. False H A L C 9 M E T H A N E 11 P E R I O D Y C D A R H Y D R O C A R B O N S C Y B G 13 D O E M O R G A N I C O N O Blackline Master #7, Post-Test 1. carbon 2. hydrogen 3. alkane 4. polymers 5. False. Organic chemistry is defined as the study of carbon compounds. Carbon, atomic number 6, has the ability to combine with other elements, which allows it to produce a vast array of chemical structures. 6. False. All alkenes have one pair of carbon atoms that have a double bond. 7. True 8. False. The hydroxyl group is the alcohols. 8 O S A X N X R Y O Y B G M 12 L B I O D E G R A D E O N N L R N K S D A S M E T H A N O L E P L A S T I C S

13 9. False. Plastics are synthetic polymers made from organic substances such as petroleum. 10. Carbon is atomic number 6. It has 4 valence electrons and it needs another 4 electrons to satisfy the octet rule. It usually does this by making four covalent bonds with other atoms. These bonds can take the form of four single bonds, two double bonds, or a triple bond with a single bond. No other element has the ability to bond in such a variety of ways. 11. In the hydroxyl group hydrogen atoms join with OH. These are the alcohols. All of their chemical names end with "ol." 12. Monomers are sub-units within polymers, which link together in long chains to make larger molecules often containing hundreds or thousands of atoms. DISCUSSION QUESTIONS 1. Is it possible to have living things that are not composed of carbon? As far as we know, the answer to that question is no. Carbon is not the only element in living things. Plants and animals have many different elements in their tissues, but the element carbon is in every molecule of every living thing. That is why it is called the element of life. 2. From where did carbon originally come? Carbon was an element that existed in the planet when the earth was formed some 4.6 billion years ago. When life first emerged in the form of a tiny prokaryotic cell about 3.5 billion years ago, carbon existed in every molecule that made up that cell. How that happened is not known, but we do know that life as we know it would not be possible without carbon. 3. What does it mean to say that the carbon atom can be linked in single, double, or triple bonds? Alkanes are hydrocarbons with only single bonds. In alkanes one electron is shared between two carbon atoms. Alkenes have a double bond between a pair of carbon atoms. In this bond two carbon atoms share two electrons. Alkynes have a triple bond between a pair of carbon atoms. In this bond two carbon atoms share three electrons. 9

14 4. Why is the burning of hydrocarbons such a serious air pollution problem? When hydrocarbons are burned, the carbon in the molecules is released into the atmosphere. It links up with oxygen to produce carbon dioxide, CO2. Since industrial production began, some 250 years ago, more and more hydrocarbons have been burned to produce energy. Today large quantities of coal are burned to produce electricity and by far the biggest hydrocarbon pollution source is the burning of gasoline in automobiles. Over the years CO2 has been building up in the atmosphere. The sun heats the surface of the earth. Much of that heat is radiated back into space, but the CO2 in the atmosphere traps the heat and reflects it back to earth, warming the planet. This is called global warming. There remains considerable debate around global warming and research is trying to determine the exact extent of the problem, but many leading scientists are convinced that global warming will disrupt weather patterns and gradually melt the polar ice caps causing a rise in sea levels that will flood the low lying areas of the world. 5. How were plastics discovered? Many materials, like steel, where discovered by metal workers hundreds of years ago through trial and error. Plastics, however, are the product of modern chemistry. Once chemists understood the way carbon linked together to make polymers they were able to replicate that synthetically. Today there are hundreds of different plastics, each with their own chemical formulas. FOLLOW-UP ACTIVITIES The following activities and projects are designed to help students understand the unique properties of carbon. 1. Draw hydrocarbon molecules showing how alkanes, alkenes and alkynes bond together. 2. Coal, limestone, diamonds, and gasoline all have carbon in their molecular structures. Research how these different substances are formed and explain their similarity and differences. 10

15 3. Write a report explaining what measures you believe should be taken to deal with the problems of global warming. Base your report on an understanding of the carbon cycle. 4. Some say the planting of trees is one of the solutions to global warming. In the international negotiations around the Kyoto Accord, countries like Russia and Canada have argued they should be given "carbon credits" for having extensive forests. Is this a ploy designed to absolve these countries of responsibility, or does it have some scientific basis? Investigate this political issue and write a report on your findings. 5. Draw a diagram that shows, in detail, the carbon cycle. Why is this cycle necessary for life on the planet? 6. Create a chart of hydrocarbons giving the proper names and chemical formulas of all substances from one carbon atom to eight carbon atoms. (Note: The prefix of the name gives the number of carbon atoms and the suffix the type of bond. The chemical formula for the each substance is derived by the general formula for each of the groups.) 7. Why is methane such a problem in landfill sites? Write a report describing the remedies that have been developed to solve this problem. 8. Why does ethanol burn cleaner than gasoline? Is this one of the solutions that could be developed to deal with air pollution? 9. Visit a plastics manufacturing plant near your home. Research the type of plastics that are being produced and the manufacturing methods that the company uses. Draw a series of diagrams illustrating the different stages of production from raw material to finished product. 10. Research the history of plastic and its present uses. What are plastic's advantages over competing materials such as steel? Will plastic eventually replace other materials or does it have limitations? Write a report on your findings. 11

16 REFERENCES There are many excellent books and websites dealing with carbon that are appropriate for students. The following is a short list. Books: Brucice, Paula Yurkanis, Organic Chemistry, Upper Saddle River, N.J., Prentice Hall, LeMay, Eugene, Karen M. Robblie, Herbert Beall, Douglas Brower, Chemistry: Connections to Our Changing World, Englewood Cliffs, New Jersey, Prentice Hall, McMurry, John, Mary E. Castellion, General, Organic and Biological Chemistry, Second Edition, Englewood Cliffs, New Jersey, Prentice Hall, McMurry, John, Robert C. Fay, Chemistry, Englewood Cliffs, New Jersey, Prentice Hall, Oxtoby, David W. and Norman N. Nachtrieb, Principles of Modern Chemistry, Fort Worth, Saunders College Publishing, Internet Sites:

17 SCRIPT OF NARRATION In the 17th and 18th centuries, when chemistry was in its infancy, researchers believed that there were fundamental differences between things that were living and inorganic materials. Living things, they felt, had some sort of vital life force. Today we know that all matter, whether living or non-living follows the same scientific principles, but there are significant differences in the chemical make up of organic and inorganic substances. CARBON: THE ELEMENT OF LIFE Organic matter, to a chemist, is any material made up of substances that are living or were once living. The element carbon is the basis of all organic substances and sometimes Organic Chemistry is defined as the study of carbon compounds. Carbon has been called "the element of life." It provides the foundation of the molecular structure of all living thing whether they are plants, animals or microorganisms. Carbon's ability to combine with other elements results in a vast array of chemical structures. Of the estimated 12 million substances that have been identified, fully 80% of them have carbon as an important part of their molecular structure. Carbon-based substances range from simple sugars to complex proteins and DNA, and even diamonds. They include fibers in the clothes we wear, almost all of the food we eat, oil, gasoline, coal, plastics, wood, graphite, limestone, coral, and marble. All of these products are composed of organisms that were once alive and all of them have carbon as an important part of their molecular structures. The secret of this unusual element lies in its atomic structure. Carbon has the atomic number of 6 and is in the second row, or period of the periodic table. It is an atom with six electrons in two energy levels. The outer shell, or valence level, has only four electrons. Elements in the second period, such as carbon, need eight electrons in order to fill the valence level. 13

18 Carbon exactly fills half of its valence level with electrons. The octet rule says that atoms tend to gain, lose or share electrons in order to acquire a full set of valence electrons. A carbon atom usually satisfies the octet rule by making four covalent bonds with other atoms. These bonds can be four single bonds, a double bond and two single bonds, or a triple bond with one single bond. Carbon is the only element that has the ability to bond in such a variety of combinations. Because carbon has only two energy levels and consequently its valence electrons are relatively close to the nucleus, carbon is able to form short, strong, stable covalent bonds. Due to these characteristics, carbon frequently links up with other carbon atoms as well as other elements like hydrogen, oxygen, and nitrogen to produce long chains of atoms. Carbon atoms provide the framework for an enormous variety of different compounds that can participate in an amazing range of chemical reactions and it is these compounds that provide the basis of life. HYDROCARBONS Chemists categorize the many different carbon substances by their molecular structures. The most simple are hydrocarbons, molecules that only contain carbon and hydrogen. Most of the earth's hydrocarbons exist in deposits of natural gas and petroleum deep in the earth's surface. We use them for a wide variety of purposes such as gasoline for running our cars, heating homes and producing electricity. Both natural gas and petroleum are formed from the remains of marine organisms that were trapped and compressed deep in the earth. That is why hydrocarbons are called fossil fuels. There are thousands of hydrocarbons. This is a molecule of methane, the simplest of the hydrocarbons. It is a highly flammable gas that is given off whenever organic material decomposes. That is why methane gas is such a problem around land- 14

19 fill sites. The chemical formula of methane is CH4, but this orbital diagram demonstrates how the molecule is structured. Carbon's four valence electrons rearrange themselves into four identical hybrid orbital shapes, keeping as far apart as possible. When the four hydrogen atoms combine with the carbon atom, the resulting molecule satisfies the octet rule because the outer shell is now full. Methane is part of the alkane family of hydrocarbons like the ones shown here and a number of others. All alkanes contain only single bonds between the carbon atoms. They are often called saturated hydrocarbons suggesting that the carbon skeletons are filled to capacity with hydrogen atoms. There can also be branched alkanes, such as this but the important thing is that the carbons are always linked with a single bond. Diagrams such as this are useful ways of understanding molecular structures but it is important to remember that these molecules are not flat, like a drawing on a piece of paper, they are three dimensional and like all molecules, are in constant motion. The general formula for alkanes is CnH2n + 2, n being the number of carbon atoms. It is easy to figure out the number of hydrogen atoms in the molecule if the number of carbon atoms is known. Butane, for example has four carbon atoms, n = 4. We get the number of hydrogen atoms by multiplying two times four and adding two. Ten. Carbon's versatility allows it to form chains of atoms but it also can form rings. When they have only single bonds they are called cycloalkanes, but they have a different formula because they have two fewer hydrogen atoms. Its general formula is CnH2n. 15

20 Saturated hydrocarbons are filled to capacity with hydrogen atoms. Unsaturated hydrocarbons are not filled to capacity. They contain a double or triple bond between carbon atoms. Apples contain ethene gas, which helps them ripen. This is the molecular structure of ethene. Note that there is a double bond between the two carbon atoms. Ethene is an example of an alkene. All alkenes have a double bond between one pair of carbon atoms and all of them have a name with a suffix of ene. The general formula for alkenes is CnH2n. There are also hydrocarbons with one triple bond. These are members of the alkyne family and all of them have a name with a suffix of yne. The general formula for alkynes is CnH2n - 2. The naming of hydrocarbons has been designed to specify the chemical structures of the substances. These are the prefixes of the names, which tells us the number of carbon atoms in the molecule. The suffix indicates the type of bond. Methane is a good example. "Meth" means the molecule has one carbon atom, and "ane" stipulates it has only single bonds. Here are some other examples. The root of the name of the compound specifies how many carbon atoms there are, and the suffix indicates the type of bonds between two of the carbon atoms. Overwhelmed with all of these names? Don't despair. The thing to understand is the pattern of the relationships. As you work with them the names will become familiar. FUNCTIONAL GROUPS Hydrocarbons are compounds containing only carbon and hydrogen but a number of organic compounds contain carbon, hydrogen and other elements. These are called hydrocarbon derivatives. There are a staggering variety of these compounds but fortunately they can be grouped into classes based on their molecular structures. These classes are called functional groups. 16

21 In halocarbons, one or more of the hydrogen atoms have been replaced by atoms from the halogen family: fluorine, chlorine, bromine or iodine. CHCl3 is structured like the methane molecule but three of the hydrogen atoms have been replaced by three chlorine atoms. This is called trichloromethane. Its name follows the pattern seen before. "Trichloro" - three chlorine atoms; "meth" - one carbon atom and "ane" - single bonds. This compound was known as chloroform, a chemical widely used as a solvent and once used as an anesthetic. There are many halocarbons. Most have chains of carbon atoms bonded to hydrogen and other atoms from the halogen group. Just as halogen atoms can substitute hydrogen atoms, so can atoms from the hydroxyl group, which contains OH. These are alcohols. There are many different alcohols and their chemical names all end in the suffix "ol." This is methanol, the simplest of the alcohol group. Again, the chemical name follows the pattern: "meth" - only one carbon atom, "an" - signifies a single bond and "ol" - an alcohol. Methanol's other name is wood alcohol. It is a dangerous substance that can be lethal or cause blindness to those that drink it. There are many different types of alcohols. Beer and wine contain ethanol, the same type of alcohol that can be blended with gasoline to produce a clean burning fuel for cars. Ethers are another group. They are molecules which contain oxygen bonded to two carbon atoms. Ethers have various applications. They were once used as an anesthetic and now are used to improve the performance of engines. When an oxygen atom is attached to a carbon atom by a double covalent bond, it is the carbonyl group. Aldehydes and ketones are in the carbonyl group and are used in the manufacture of plastics and adhesives. 17

22 Two oxygen atoms can also bond to the same carbon atom, which creates groups called carboxylic acids and esters and there are several classes of organic compounds produced when carbon combines with nitrogen. These classes are called amines and amides. Carbon can enter into a large number of other molecular arrangements to form a variety of common organic compounds. POLYMERS AND PLASTICS Organic polymers are macromolecules with a backbone of carbon atoms. They are closely linked to hydrocarbons, but they can combine with other elements such as oxygen, fluorine, nitrogen, silicon, phosphorous and sulfur. They are made up of sub-units called monomers, which link together in long chains to make larger molecules often containing thousands or even millions of atoms. Long chains of polymers provide structural strength to plants in such things as tree trunks and stems of flowers, but scientists have also used their knowledge of chemistry to create synthetic polymers we call plastic. The first synthetic polymer was bakelite, which was marketed in Rayon soon followed and nylon was developed in the 1930s but it was during the Second World War that a wide range of plastics was first produced. Today plastics made from petroleum, an organic compound, with other elements added to give the desired physical properties, are used in an enormous number of products from children's toys, to home furnishings and parts of automobiles. They are inexpensive, easy to mold and shape, do not corrode, can be colored, resist pests such as termites and can be made to be structurally very strong. Plastics are truly a miracle product of our age, but their widespread use has created new problems. Plastic does not biodegrade easily. The strength of the molecular bonds means that plastics decompose very slowly. Every year millions of tons of 18

23 plastic waste are being dumped into landfill sites causing massive environmental problems. LIFE PROCESSES The life processes in all living organisms involve thousands of chemical reactions that happen continuously. Respiration, digestion, reproduction, the circulation of blood, metabolism, all of these processes and more are chemical processes. These areas are the subject of study of biology and biochemistry but scientists working in these areas must understand chemistry in order to understand these life processes. Perhaps the most fundamental of all life processes is photosynthesis, a complex chemical process that occurs in plants and some microorganisms, in which light energy from the sun is converted into chemical energy that can be used by the plant and animals further along the food chain. In the cells of plant leaves are tiny organelles called chloroplasts, which give the green color to leaves. In the chloroplasts, carbon dioxide from the air is combined with water and sunlight to produce glucose, a type of sugar. It is then converted into other chemicals, which can be used as energy by cells in living organisms. A byproduct of the photosynthesis process is oxygen, O2, which is released into the atmosphere. Virtually all of the oxygen in the atmosphere, which is essential for the life of all animals, was produced through this process. But animals are also indebted to the cells of plants and algae in another way. When animals eat plants they gain the glucose, starch, carbohydrates and other foods that are essential for them to survive. Even carnivores that never eat plants get these nutrients by eating animals that have eaten them. It is in the chemistry of living things that life itself is sustained and maintained. Not only could living things not exist without these chemical processes, but life itself would also not be possible without the simple element of carbon. 19

24 1 CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Pre-Test Name Directions: This will help you discover what you know about the subject of matter before you begin this lesson. Answer the following true or false. 1. Carbon is in all molecules of every living thing. T F 2. Carbon's atomic number is 5. T F 3. The octet rule states that atoms tend to gain, lose, or share electrons in order to acquire a full set of valence electrons. T F 4. Carbon can only link with other carbon atoms in single bonds. T F 5. Hydrocarbons are composed of carbon, hydrogen, and other elements. T F 6. Methane gas is a hydrocarbon. T F 7. All hydrocarbons with the prefix of "oct" have molecules with eight carbon atoms. T F 8. Halocarbons have oxygen atoms. T F 9. Plastics are made from organic compounds. T F 10. Photosynthesis is a fundamental life process carried out by plants and some microorganisms. T F 2003 Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.

25 2a CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Vocabulary Definitions Name The following words and terms used in the program may be unfamiliar to you. Try to listen for these terms while viewing the program, pay close attention so you can later include them in your scientific descriptions, observations, and creative writing assignment activities. aldehydes - A compound in the carbonyl group. alkanes - Hydrocarbons where the carbon atoms are linked with a single bond. alkenes - Hydrocarbons where one pair of carbon atoms are linked with a double bond. alkynes - Hydrocarbons where one pair of carbon atoms are linked with a triple bond. atom - The fundamental unit of matter in the universe made up of a nucleus of protons and neutrons and orbiting electrons. atomic number - The number of an element, determined by the number of protons in its nucleus. biodegrade - Decompose. carbon - Element with the atomic number of 6 and the symbol of C. carbon dioxide - CO2. In the atmosphere carbon dioxide is the most important greenhouse gas. carbonyl group - A functional group with an oxygen atom attached to a carbon atom by a double covalent bond. chemical reactions - A change in the chemical composition of a substance. compounds - When valence electrons of elements are lost, gained, or shared between different atoms to create substances with unique chemical properties. cycloalkane - Alkanes whose molecules are formed in a ring double bond - Compounds with a pair of atoms sharing two electrons. electrons - Negatively charged particles that orbit the nucleus of atoms. element - An atom with a unique number of protons. energy - In physics and chemistry, energy is work, or the capacity to do work. energy levels - Electrons orbit the nucleus of atoms with different levels of energy. These energy levels are sometimes called shells or levels. ethane gas - An alkane hydrocarbon. ethanol - The alcohol in alcoholic drinks. A type of ethanol can be blended with gasoline. fossil fuels - Fuels composed of organic compounds. functional groups - Classes of hydrocarbon derivatives. halocarbons - A functional group where one or more of the hydrogen atoms are replaced by atoms from the halogen family: fluorine, chlorine, bromine, or iodine. hydrocarbon derivatives - Compounds containing carbon, hydrogen, and other elements. hydrocarbons - Molecules that only contain carbon and hydrogen. hydrogen - The element with the atomic number of 1 and the symbol of H. Hydrogen is the most common element in the universe. hydroxyl group - A functional group that contains OH. These are the alcohols. ketones - A compound in the carbonyl group. matter - Material that makes up objects. Matter cannot be created or destroyed. methane - The simplest hydrocarbon, CH4 methanol - The simplest of the alcohol group, often called wood alcohol. molecules - When electrons are shared between atoms. Molecules have covalent bonds. monomers - Sub-units of polymers, which can link into long chains. octet rule - Atoms tend to gain, lose, or share electrons in order to acquire a full set of valence electrons. orbitals - The shapes of the orbits of electrons. organic chemistry - The study of carbon compounds. oxygen - The element with atomic number of 8 and the symbol of O. period - Horizontal rows of the periodic table. periodic table - The arrangements of elements according to their atomic number and group. photosynthesis - A complex chemical process that occurs in the leaves of plants and some microorganisms in which light from the sun is combined with water to produce chemical energy that can be used by plants and animals. In the process oxygen, O2, is released into the atmosphere. plastics - Synthetic polymers. polymers - Compounds with a backbone of carbon atoms. Polymers are made up of subunits called monomers, which link together in long chains to make larger molecules. proton - Positively charged part of the nucleus of atoms saturated hydrocarbons - The molecules in these hydrocarbons are filled to capacity with hydrogen atoms. single bond - Compounds with a pair of atoms sharing one electron. triple bond - Compounds with a pair of atoms sharing three electrons unsaturated hydrocarbons - The molecules in these hydrocarbons are not filled to capacity with hydrogen atoms. valence electrons - The outer ring of electrons of an element. nucleus - The center of an atom Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.

26 2b CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Use the Right Word Name Directions: Find the right word from the vocabulary list that completes the following sentences. 1. The study of carbon compounds is called chemistry. 2. The element has the atomic number of A has molecules containing only carbon and hydrogen. 4. Hydrocarbons, where the carbon atoms are linked with a single bond, are called. 5. The functional group, where one or more of the hydrogen atoms are replaced by atoms from the halogen family, are called. 6. The alcohols are in a functional group called the group. 7. All fuels are composed of organic compounds. 8. Polymers are made up of subunits called, which link together into long chains to make larger molecules. 9. The life processes in all living things involve thousands of chemical that happen continuously. 10. The process that occurs in the leaves of plants and some microorganisms in which light from the sun is combined with water to produce energy, which can be used by plants and animals and O2, which is released into the atmosphere, is called Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.

27 2c CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Word Match Name Directions: Connect the word with the proper definition. alkenes alkynes biodegrade carbon hydrocarbon hydrogen hydroxyl synthetic polymers molecules containing carbon and hydrogen can link into long chains group containing alcohols carbon atoms linked with a double bond decompose carbon atoms linked with a triple bond methane element with atomic number of 1 monomers simplest hydrocarbon, CH4 plastics element with atomic number of Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.

28 3 CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Connected/Not Connected Name Directions: Place the following words in the proper sentences. alkanes ethanol methane organic alkenes halocarbon methanol plastics biodegradable hydrogen monomers polymers carbon hydroxyl octane propane ethane living things octyne propyne 1. chemistry is connected to because it is the study of living things or things that were once living. 2. are NOT connected to because one family of compounds contain only single bonds between the carbon atoms and the other family of compounds contain a pair of carbon atoms linked by a double bond. 3. atoms are connected to atoms because only these two elements are in hydrocarbons. 4. is NOT connected to because one has one carbon atom and the other has two carbon atoms. 5. is connected to because both have eight carbon atoms. 6. is NOT connected to because, although both have three carbon atoms, in one, the carbon atoms are connected with single bonds, and, in the other, two of the carbon atoms are connected with a triple bond. 7. is connected to because both are alcohols and are in the hydroxyl group. 8. The group is NOT connected to the group because one group is made up of molecules where some of the hydrogen atoms are replaced with atoms from the halogen family, and, in the other, the hydrogen atoms are replaced by OH atoms. 9. are connected to because they are made up of sub-units which link together in long chains to make larger molecules often containing thousands or millions of atoms. 10. are NOT connected to substances because the strength of their molecular bonds means they do not break down easily Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.

29 Name 4 CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Crossword Puzzle Across 3. Contains OH. 4. Some hydrogen atoms replaced by atoms from the halogen family. 5. Links between atoms. 7. Atomic number Atomic number Atomic number Hydrocarbons with carbon atoms linked by single bonds. 13. Sub-units of polymers. Down: 1. Horizontal row of the periodic table. 2. chemistry. 3. made up only of carbon and hydrogen atoms. 5. Decompose. 6. Synthetic polymers. 8. Simplest of the alcohol group. 9. Simplest of the hydrocarbons Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.

30 Name 5 CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Creative Writing Story Ideas Directions: Choose from one of the ideas listed below and write a story or dramatization. Include plot lines that follow scientific principles and key vocabulary terms Create a dialogue between two characters. One of the characters has a pre-scientific view and believes that all living things have a vital life force, while the other takes the scientific point of view that all matter, whether it is organic or inorganic, follows the same scientific principles. 2. Write a science fiction story about a character born without carbon in his or her molecules. 3. Write a long poem that humorously plays with hydrocarbon prefixes and other organic chemistry names. 4. You are a member of a student group fighting air pollution and have been asked by city council to make proposals to reduce CO2 emissions. You have written your speech and nervously wait to address the councilors when another group enters the council chambers intent on disrupting your remarks. Describe what happens. 5. Write a film script about a scientist and his or her assistant who are trying to invent a new plastic automobile Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.

31 6 CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Video Quiz Name Directions: Answer the following either true or false, or fill in the blank with the correct word to make it true. 1. All matter follows the same principles but there are significant differences in the chemical make up of organic and inorganic substances. T F 2. The element carbon provides the foundation of the molecular structure of every living thing whether they are plants, animals or microorganisms. T F 3. Carbon has the atomic number of 7 and is in the third period of the periodic table. T F 4. Because of its characteristics carbon frequently links up with other carbon atoms and other elements. T F 5. Hydrocarbons are molecules of carbon, hydrogen, and other elements. T F 6. Methane is the only alkane. T F 7. A number of organic compounds contain carbon, hydrogen, and other elements. They are called hydrocarbon derivatives. T F 8. Plastics are made from inorganic material and never contain the element carbon. T F 9. The life processes in all living organisms involve thousands of chemical reactions that happen continuously. T F 10. Animals perform photosynthesis in their cells. T F 2003 Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.

32 7 7 CARBON: THE ELEMENT OF LIFE from the Elements of Chemistry Series Post-Test Directions: Fill in the blank with the appropriate term from the list below. alkane carbon functional organic alkene carbonyl hydrocarbons oxygen alkyne cycloalkane hydrogen photosynthesis atomic electron methane polymers bond element molecules propane Name 1. Organic chemistry is defined as the study of compounds. 2. Hydrocarbon molecules only contain carbon and atoms. 3. The family of hydrocarbons contain only single bonds between the carbon atoms. 4. Chemists have been able to make synthetic called plastic. Directions: Fill in the blank with True or False. If the statement is false, change it to make the statement true. Rewrite the true statement in the space provided. 5. Organic chemistry is defined as the study of hydrogen compounds. 6. The alkene family of hydrocarbons contain only single bonds between the carbon atoms. 7. In halocarbons, one or more of the hydrogen atoms have been replaced by atoms from the halogen family. 8. The hydroxyl group include all of the sugars. 9. Plastics are organic polymers. Essay Section Directions: Answer the following questions in complete sentences. Use the back of this page or a separate sheet of paper if you need more space to complete your answer. 10. Explain why carbon has the ability to unite with so many other elements. 11. Describe the hydroxyl group. 12. What are monomers? 2003 Algonquin Educational Productions Published and Distributed by United Learning All rights to print materials cleared for classroom duplication and distribution.