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Section 2.1 - Organic Compounds Where do you find organic compounds? Fertilizers Herbicides Pesticides Compounds composed of carbon Simplest type of organic compound is a hydrocarbon.

1 Section Organic Compounds Where do you find organic compounds? Fertilizers Herbicides Pesticides Compounds composed of carbon Simplest type of organic compound is a hydrocarbon. Contain carbon & hydrogen Which of the above are saturated? Unstaurated? Single bonds = saturated (i.e. butane) Double bonds & triple bonds = unsaturated Ethene = double bond Ethyne = triple bond Alkane - "ane" = single bonds Alkene - "ene" = double bonds Alkyne - "yne" = triple bonds File Attached Steps: 1. Determine suffix 2. Name longest chain. 3. Locate position of multiple bond. 4. Locate & Name branches 5. Combine all parts Hydrocarbons with aromatic or phenyl or benzene rings = cyclical Ex. Benzene C 6 H 6 = Hexagonal

2 Benzene Component to gasoline - restricted in %age because it is: Carcinogenic Concerns with leaching if spilt in water or soil. Cleaned up with remediation; although benzene is difficult to break down. Why? Ring structure is stable/resonance PAHs - polycyclic aromatic hydrocarbons Produced by incomplete combustion of oils from foods and from diesel emissions. Can interact with DNA and potentially cause mutations. Use low-temp grill to reduce flare-ups and the PAHs present in food. Persistent organic pollutant (POP) Synthetic Organic Molecules - Human made organic compound Functional Group - An arrangement of single atoms or groups of atoms, other than carbon or hydrogen, attached to an organic molecule. THE DATABOOK IS YOUR FRIEND HERE!! Halogenated Hydrocarbons What are the halogens? Group 17 - A hydrocarbon that has one or more hydrogen atoms replaced by atoms of chlorine, fluorine, bromine or iodine. Naming Halogenated Hydrocarbons Steps: 1. Name parent chain. 2. Locate halogen substituents. 3. Determine position, number and name of substituents. 4. Name it Page 251 Ex. CFC = Chlorofluorocarbon

Page 252 Page 252 Attached File Work through

CFCs & OZONE (O 3(g) ) Invented in the 1920s.

air-conditioners & refridgerators Destroy

of the stratosphere, (the portion of the

3 Page 252 Page 252 Attached File Work through as a class! CFCs & OZONE (O 3(g) ) Invented in the 1920s. Nonflammable, nontoxic Used in air-conditioners & refridgerators Destroy the ozone layer The ozone layer is a portion of the stratosphere, (the portion of the atmosphere between 10 km and 50 km above Earth s surface.) m Website Link

Ozone, O 3(g), is produced and decomposed in a natural process involving UV radiation and O 2(g) in a cycle, as follows: Production of O 3(g) O 2(g) + UV energy greater than 8.

4 Ozone, O 3(g), is produced and decomposed in a natural process involving UV radiation and O 2(g) in a cycle, as follows: Production of O 3(g) O 2(g) + UV energy greater than 8.25 x J yields 2 O (g). O (g) + O 2(g) in the presence of a catalyst yields O 3(g). This cycle maintains a steady level of O 3(g), which protects the Earth from exposure of excessive levels of ultraviolet radiation from the Sun. The Sun emits energy in the form of radiation, including visible light, infrared radiation and ultraviolet radiation, etc. UV radiation is harmful because it can cause damage to living tissue. It possesses more energy than visible light or other forms of radiation and can excite molecules and initiate chemical reactions. Decomposition of O 3(g) O 3(g) + UV energy (between of 6.22 x J x J) yields O 2(g) + O (g). It was discovered that freed Cl, or a free radical, from CFCs in the atmosphere, caused the depletion of the ozone layer, as follows: Animation Free radicals can also have a damaging effect on your body. -chemicals that have an unpaired electron in the valence shell. - react easily with other substances to fill the valence shell. - exposure to radiation or substances in food, may result in the production of oxygen-containing free radicals, which can react with lipids, proteins, and DNA affecting the function of body cells. These oxygen-containing free radicals can be reduced by including antioxidants in your diet -vitamin E -vitamin C - beta-carotene - lycopene These antioxidants prevent the oxidation reaction that produces free radicals of oxygen.

5 Ozone Depletion and Environmental Concerns The Montreal Protocol is an international agreement to cease the production of CFC s and to replace it with less harmful HCFC s which contain fewer Cl atoms or HFC s which do not contain any chlorine atoms. Also, the thickness of the ozone layer is monitored throughout the year to assess damage. Biomagnification and Halogenated Hydrocarbons Many herbicides and pesticides contain halogen atoms and are a health concern because of their effect on your body, (the central nervous system, heart, liver, and kidneys) and accumulate through biomagnification Ex. PCBs Ex. DDT Although other halogenated hydrocarbons are also destructive to the ozone layer, they are not restricted in the Montreal Protocal because there is no viable alternative for this chemical. Ex. methylbromide, a pesticide Ex. Halon 1211, a fire retardant used in airplanes. Ex. tetrachloromethane (carbon tetrachloride) used as a cleaning solvent until it was found to be carcinogenic Ex. polyvinyl chloride,(pvc) used to make garden hoses and floor tile. Others and their structures are on page 259 in your textbook. Section 2.2 Alcohols, Carboxylic Acids, and Esters Example: Methanol (wood alcohol) 1. Alcohols - organic molecules that contain a hydroxyl functional group (R-OH) - soluble in water - polar molecules - found in solvents, fuels, pharmaceutical production & disinfectants. - ingesting methanol will cause blindness or be fatal because enzymes in your liver will break it down into very toxic compounds.

Example: Glycol Example: isopropanol - found in solvents - found in disinfectants Example: Ethanol - found in solvents, fuels, alcoholic beverages, production of pharmaceuticals, disinfectants - made

6 Example: Glycol Example: isopropanol - found in solvents - found in disinfectants Example: Ethanol - found in solvents, fuels, alcoholic beverages, production of pharmaceuticals, disinfectants - made for at least 6000 years by adding yeast to solutions that are rich in either sugars or starches. The yeast cells obtain energy from enzyme-catalyzed reactions that convert sugar or starch to ethanol and CO 2(g). Naming Alcohols Steps: 1. Find hydroxyl group 2. Determine parent chain starting at nearest to hydroxyl group 3. Determine parent name. 4. Communicate location of hydroxyl group 5. Use sufiix "ol" C 6 H 12 O 6(aq) ---->2 CH 3 CH 2 OH (aq) + 2 CO 2(g) [Fermentation]

7 2. Carboxylic Acids - a carbonyl functional group is formed by the joining of an oxygen atom to a hydrocarbon by a double bond R=O. - a carboxylic acid is a functional group formed by the joining of a single C atom to a single O atom with a double bond and a hydroxyl group OH (or alcohol) with a single bond R-COOH - Carboxyl groups have the carbonyl group and the hydroxyl group Examples: - Vinegar - Citrus Fruit - Vitamin C Example: PABA - para-aminobenzoic acid Benzene and carboxylic acid together Naming Carboxylic Acids: Steps: 1. Locate parent chain 2. suffix is "oic acid" - Found in sunscreen - Benzene can absorb the UV rays - some people are allergic to PABA LINK to UNIT A -- Immunity & Anaphylactic shock

3. Esters Alcohols and carboxylic acids react to form

removing the H from the alcohol and the OH from the

The product of this reaction is an ester.

One type is a polymer called polyester, which is a

8 3. Esters Alcohols and carboxylic acids react to form esters Esters usually have a pleasant odor and are the flavor for many foods. Esterification is the process of creating an ester by removing the H from the alcohol and the OH from the hydroxyl group in the carboxylic acid. The product of this reaction is an ester. Polyesters There are many different types of plastics. One type is a polymer called polyester, which is a polymer of many ester functional groups. It is created from the reaction of many alcohols and carboxylic acids forming long chains or filaments.

9 a disadvantage of plastics is that they are non-degradable. Modern technology is using bioplastics which are degradable. Made of naturally occurring compounds - can be broken down by bacteria Polymer - a large molecule made up of many small and identical submolecules. Ex. Silk Ex. Sap - put together like a string of beads Made from polyester of corn, soy, hemp or bacteria Synthetic Polymers - manmade - characteristics we want Ex. plastics Section 2.3 Understanding Exposure Many organic products have been produced to benefit mankind, however some organic compounds or their by-products have turned out to have harmful side effects. 1. VOC s or volatile organic compounds Off-gassing is an important environmental concern and is the release of volatile organic compounds (VOCs) from building materials such as paints, treated lumber and flooring, wall coverings, etc. To reduce exposure: *use materials that do not contain VOCs *avoid direct contact by using gloves, etc. *work in well ventilated areas

2. Pesticides A pesticide is a substance that is used to kill fungi, insects, animals or plants considered as pests. Considerations when using a pesticide: 1.

10 2. Pesticides A pesticide is a substance that is used to kill fungi, insects, animals or plants considered as pests. Considerations when using a pesticide: 1. Specificity Target specificity is the range of organisms affected by the pesticide. It is important to chose the pesticide that is targeted for a specific pest. Broad Spectrum pesticide is a chemical substance that can control the population of a large variety of organisms. Page 282 Toxicity is the ability to cause damage to living tissue, impair the function of a body system or cause death when injested, inhaled, or absorbed. Toxicity is rated according to LD 50 and LC 50. LD 50 is the dosage of a chemical substance, given all at once, that kills half (50%) the population tested within a specified time. LC 50 is the concentration of a chemical substance in air or water that kills half (50%) the population tested within a specified time. 2. Combined Effects There is a concern regarding the effects that combinations of organic compounds used in pesticides may have on the environment and on humans. For example, absorption of some pesticides through the skin is higher when sunscreens are worn. The values are expressed in mg/kg. Regardless of toxicity, pesticides should not affect non-target organisms. Ex. 2,4 D (2,4-dichlorophenoxyethanoic acid)

11 3. Drift, Grasshopper Effect and Resistance Drift is the transfer of the pesticide by wind or air currents from the location where it was sprayed. Grasshopper effect is the transport of pesticides that result from the evaporation in warmer climates and condensation in colder climates. Ex. pesticides are being detected in the Arctic. 4. Water Quality Water quality can be affected by acid deposition, persistent organic compounds, and the leaching of metal ions, and fertilizers or organic matter. -- Can result in Algal Blooms Persistence is the resistance of a chemical substance being broken down by biological or chemical means. Soil micro-organisms can act on pesticide molecules---using them as a source of carbon for their own growth. However, pesticides containing halogenated hydrocarbons or benzene rings cannot be easily broken down. As a result, these pesticides remain in the water, air and soil and through biomagnification result in toxic effects for organisms higher up in the food chain. Ex. Algal bloom - leaching of fertilizers and organic matter, rich in nitrogen and phosphorous, from fields into surface water adds additional nutrients which encourage the rapid growth of algae. -toxins produced by the algae may be harmful to humans and animals. - decomposition of the algae on the surface affects the oxygen content in the water which can result in a winterkill of fish species in the water. - Biochemical or Biological Oxygen Demand (BOD) is a measure of the amount of oxygen required for the decomposition of organic matter. The test consists of comparing the dissolved oxygen concentration of a sealed water sample. A decrease in the concentration of dissolved oxygen occurs when micro-organisms decompose organic matter. Water samples containing high levels of organic matter (high BOD) demonstrate a large reduction in dissolved oxygen concentration. Thus water contaminated with organic matter from human or animal waste may have a high BOD or may serve as a source of nitrogen and phosphorous that promotes the growth of algal bloom. 5. Resistance A resistant population is a group of organisms not affected by a pesticide. Genetic principles, including mutations, create variations in a population and this variation can result in some members of a population possessing resistance to a pesticide. As a result, only members resistant to a pesticide will survive. Breeding between resistant and non-resistant populations tend to result in offspring that are resistant. Thus pest control practices designed to kill higher percentages of pest population results in a faster development of resistant pest populations.

12 So what can be done? 1. Governments are involved in the management of chemical substances. 2. Rather than using pesticides, there are alternative methods to control pests:

Chapter 9. Organic Chemistry: The Infinite Variety of Carbon Compounds. Organic Chemistry

Chapter 9. Organic Chemistry: The Infinite Variety of Carbon Compounds. Organic Chemistry Chapter 9 Organic Chemistry: The Infinite Variety of Carbon Compounds Organic Chemistry Organic chemistry is defined as the chemistry of carbon compounds. Of tens of millions of known chemical compounds,