Organic chemistry is the study of compounds that contain CARBON
Transcription
Organic chemistry is the study of compounds that contain CARBON
5.3 Organic Compounds Which of the following compounds do you think are organic? vinegar gasoline olive oil acetone cork charcoal alcohol polyester wood propane wool plastic laundry detergent nylon paper rubber cotton nail polish Round-up weed motor oil leather killer All of the above compounds are organic! Some inorganic compounds include: table salt all metals ionic compounds metal alloys most “rocks” glass minerals concrete clay I. What is Organic Chemistry? Short answer: NOT what the name “organic” implies! • Organic chemistry is the study of compounds that contain CARBON. • This means all organic compounds contain carbon! • Almost all carbon-containing compounds are organic • This includes both natural and synthetic (manmade) compounds • Inorganic compounds generally DO NOT contain carbon Exceptions: CO, CO2, and compounds containing CO3 are all inorganic • Carbon: – is very versatile due to its 4 valence electrons. (allows for 4 bonds) C + 4H H H C H H – is usually bonded to H, O or other non-metals – can bond with itself to form long chains of carbon atoms (eg: petroleum & plastics) • Organic compounds always have C before H in their formulas (eg: CH4) Summary: Carbon forms so many different compounds that a whole branch of chemistry is dedicated to it! II. Some Types of Organic Compounds Hydrocarbons = Organic compounds that contain only C and H atoms polyethylene • • C5000H10000 plastic Hydrocarbons are flammable and many are used as fuels See table 5.8 (page 247 in textbook) or page 96 in workbook Question: Can C5000H10000 be reduced to CH2? (divide both subscripts by 5000) Answer: No, because C5000H10000 is a covalent compound. IONIC Na1Cl1 Na2Cl2 Na5Cl5 Na50Cl50 Na100Cl100 These are ALL correct so we use the most reduced one, NaCl. Subscripts can only be reduced in ionic chemical formulas, because ionic compounds are made up of a pattern of atoms that repeat over and over in a crystal lattice structure, so only the ratio of the different atom types matters. COVALENT The material is made up of a bunch of individual CH4 molecules. They’re NOT C2H8 molecules or C10H40 molecules, and it would be wrong to call them that. But covalent chemical formulas can’t be reduced because they represent an actual molecule and the subscripts represent the exact number of atoms in the molecule. If you reduce the subscripts, you’re talking about a different molecule! Alcohols = organic compounds that contain C, H and O atoms • All alcohols are poisonous and flammable • See table 5.9 (page 248 in textbook) or page 97 in workbook III. Ways to Represent Organic Molecules In your notes, represent CH4 with its molecular formula and structural formula, and with the ball-and-stick model and space-filling model. Can you figure out which is which? See workbook p.95 for help. Homework: 1) Text p.247 #1-5 2) Workbook Pages 98-99, 101