Transcript Slide 1
Chapter 21 Section 1—Simple Organic Compounds Organic Compounds • Organic compounds— compounds containing carbon • All living things contain carbon • Of the millions of carbon compounds known today, more than 90 % are considered organicthe other 10% are found in nonliving things Bonding • Carbon has four electrons in its outer energy level • Each carbon can form four covalent bonds w/atoms of carbon or other elements • Common uses: fuel, medicines, dyes, plastics, textile fibers Arrangement • Carbon can also link together with other carbon atoms in many different arrangements: chains, branched chains and rings • It can also form double and triple bonds as well as single bonds Hydrocarbons • Hydrocarbon—a compound made up of only carbon and hydrogen atoms • Ex: CH4-methane (rep-pg. 641) • Ex: propane • Hydrocarbons produce more than 90% of the energy humans use Single Bonds • Saturated hydrocarbons—those containing only single-bonded carbon atoms • This means the compound holds as many hydrogen atoms as possible—it is saturated • (saturated fats) • Table—pg. 642 Structural Isomers • Butane—C4H10 • Isobutane—also C4H10 • These two fuels have different arrangements of the four carbon atoms (pg. 643) • Isomers-compounds that have identical chemical formulas but different molecular structures and shapes Other Isomers • Properties of isomers may vary greatly – Ex: melting points can vary drastically Sometimes, isomers form what is often called right and left-handed molecules like mirror images w/nearly identical properties Multiple Bonds • Unsaturated Hydrocarbons— hydrocarbons that contain at least one double or triple bond – This allows space for other atoms to bond to the structure – Ex: ethene C2H4-contains a triple bond – Polyunsaturated-hydrocarbons having more than one double or triple bond – (poly means many) Section 2—Other Organic Compounds • Aromatic Compounds-one that contains a benzene structure having a ring with six carbons • Ex: cloves, cinnamon, anise, vanilla, aspirin, wintergreen • Benzene—has six carbon atoms bonded into a ring Benzene Ring • Look at picture—pg. 646 • The Benzene ring is structurally stable due to the equal sharing of electrons • All six carbon atoms are bound in a rigid, flat structure • The stable ring acts as a framework upon which new molecules can be built Substituted Hydrocarbons • -has one or more of its hydrogen atoms replaced by atoms or groups of other elements. • (chemists change hydrocarbons by changing them into other substances (adding double bond, etc) Alcohols and Acids • Ex: Rubbing alcohol-substituted hydrocarbon • An ALCOHOL is formed when –OH groups replace one or more hydrogen atoms in a hydrocarbon • Ex: ethanol More on Alcohols and Acids • Organic acids—form when a carboxyl group, -COOH is substituted for one of the hydrogen atoms attached to a carbon atom. • Ex: acetic acid, citric acid, lactic acid, etc. Substituting Other Elements • Other atoms besides hydrogen and oxygen can be added to hydrocarbons • Ex: Chlorine-when four chlorine atoms replace four hydrogen atoms, = tetrachloroethene (used in dry cleaning More on subbing other elements Other possibly substituted atoms are: nitrogen, bromine, sulfur, etc. When sulfur replaces oxygen in the –OH group of an alcohol, the result is a –thiol or more commonly, a mercaptan (in skunk smell) Section 3--Petroleum • Petroleum—a dark flammable liquid/crude oil found deep within Earth – Formed from the remains of fossilized material—fossil fuel – A mixture of thousands of carbon compounds Separation of Petroleum • Chemists and engineers separate petroleum using the different boiling points of the different carbon compounds in petroleum • Fractional distillation-the separation process that takes place in petroleum refineries Fractional Distillation • Figure 13, pg. 651 • Illustrates fractional process • Some fractions are used directly for fuel—those from the top of the tower ex: propane, butane • The fractions containing 5 to 10 carbons are used for gas and solvents Polymers • Polymers—when smaller molecules from petroleum link together, to make new, extremely large molecules • Monomer—small molecule, which forms a link in the polymer chain • Ex: Polyethylene-plastic bags, bottles and Polypropylene—glues and carpets Designing Polymers • The properties of polymers depend mostly on which monomers are used to make them • Like hydrocarbons, polymers can have branches in their chains • Ex: polystyrene—used for CD cases and opaque foam cups, • Other polymers can be spun into threads to be used as fibers Other Petroleum Products • After petroleum is separated, the different fractions can be converted into substituted hydrocarbons • Ex: medicines, insecticides, printers’ ink and flavorings • Ex: saccharin (related to toluene, a substituted benzene ring) Section 4-Biological Compounds • Biological polymers—huge molecules made of many smaller monomers that are linked together, but usually more complex in structure • Ex: carbohydrates, proteins, lipids Proteins • Proteins—large organic polymers formed from organic monomers called amino acids • Proteins account for 15 % of body weight (muscles/tendons/hair,etc) • Amino Acids—protein monomers that combine to form proteins More about proteins • -NH-2 group is the amine group • -COOH group is the carboxylic acid group • Both groups appear in every amino acid • Amino acids are held together by peptide bonds (50 or more held together is then a protein) Nucleic acids • Nucleic acids—another important group of organic polymers essential for life/ – They control the activities and reproduction of cells – DNA—deoxyribonucleic acid—one kink of nucleic acid (in nucleus of cells, contains genetic code) Carbohydrates • Carbohydrates—compounds containing carbon, hydrogen, and oxygen that have twice as many hydrogen atoms as oxygen atoms • Carbohydrates include the sugars and starches Carb’s-Sugars and Starches • Sugars—ex: fructose, glucose – They provide quick energy soon after eating Starches—ex: pasta, potatoes, etc. Provide high-energy, long-lasting energy that can be stored in liver and muscle cells LIPIDS • Lipids—fats, oils and related compounds • They contain the same elements as carb’s, but in different proportions • Fats/Oils: At room temp, fats are normally solids and oils are usually liquids • Cholesterol: found in fish, eggs, butter, cheese, meats, bile • If you never eat cholesterol, your body will make its own