Organic Chemistry

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Organic Chemistry Organic Chemistry Today’s Objectives: 1) Define organic compounds as compounds containing carbon, recognizing inorganic exceptions such as carbonates, cyanides and carbides 2) Identify and describe significant organic compounds in daily life, demonstrating generalized knowledge of their origins and applications 3) STS: Demonstrate an understanding that science and technology are developed to meet societal needs and expand human capability Unit A: Chapters 9 and 10 Organic Introduction Today’s Agenda: 1) Introduce organic chemistry and review the origins and applications of some major organic compounds 2) “Carbon – The element of life” video 3) Are You Ready pg. 354 #1-6 – due tomorrow Section 9.1 (pg. 354-361) What is Organic Chemistry? The early definition related to compounds obtained only from living things. Today, it is a major branch of chemistry that deals with compounds of carbon, called ORGANIC compounds*. *Carbon compounds that are exceptions and considered INORGANIC are compounds like: Oxides carbon monoxide (CO(g) ) and carbon dioxide (CO2(g) ), and 2- Ionic compounds of carbon-based ions, such as carbonate CO3 , cyanide CN-, and carbide ions, SiC (silicon carbide) The major source of carbon compounds is still living or previously living things, such as plants, animals and all types of fossil fuels. Organic or Inorganic?? Formula Organic or Inorganic? CaCO3(s) Inorganic (carbonate ion) C25H52(s) Organic Ca2C(s) Inorganic (carbide ion) CCl4(l) Organic CH3COOH(l) Organic CO2(g) Inorganic (oxide) KCN(s) Inorganic (cyanide) C12H22O11(s) Organic Why is carbon special? There are millions or organic compounds and only a thousand inorganic compounds. WHY? Carbon has a bonding capacity of 4 Remember Lewis Dot Diagrams from Chem 20?? This means carbon can bond extensively and can bond together to form chains effectively = called Polymerism Carbon covalently bonds by sharing 4 pairs of electrons. These bonds may be single, double or triple, all producing stable compounds Compounds can form with same number of each type of atom but different structures = Isomerism Determining Lewis Formulas So why do we care about bonding capacity? If we know how many bonding e-’s an atom has, we can predict what structure a molecular compound will have Atom Number of Number of Bonding capacity valence electrons bonding electrons carbon 4 4 4 nitrogen 5 3 3 oxygen 6 2 2 halogens 7 1 1 H hydrogen 1 1 1 I.e. Carbon can form 4 single bonds, 2 double bonds, 1 triple and 1 single, or 1 double and 2 singles Polymers Examples of repeating carbon chains: Isomers Compounds with the same number of each type of atom but different structures (C4H10) We will talk about this in more detail later Importance of Organic Chemistry Building units of all living matter: carbohydrates, proteins, fats All foods are organic compounds Photosynthesis is a reaction that makes carbon a part of our food. Carbon is passed along through food chains and sugar from photosynthesis is modified and combined with other materials. Dead organisms are food for other organisms, or are buried in the earth and converted to fossil fuels like peat, coal and petroleum Petroleum is the source of fuel and starting material for plastics, fabrics and industrial chemicals The carbon cycle is an illustration of the interrelationship of all living things with the environment and with technologies that refine and use fossil fuels We will continually outline the importance of organic compounds in our daily lives Carbon: The Element of Life Complete the worksheet provided as you watch the following video (20 min) .
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