1. Chapter 4. The Chemistry of Carbon

2. Why study Carbon? All living things are made of cells Cells ◦~72% H 2 O ◦~3% salts (Na, Cl, K…) ◦~25% carbon compounds ◦ carbohydrates ◦ lipids ◦ proteins ◦ nucleic acids 2003-2004

3. Chemistry of Life Organic chemistry is the study of carbon compounds C atoms are versatile building blocks ◦bonding properties ◦4 stable covalent bonds - pair of electrons are shared 2003-2004

4. Complex molecules assembled like – candy & toothpicks

5. Hydrocarbons Simplest Carbon molecules = hydrocarbons ◦A compound with a combination of Carbon & Hydrogen Simplest HC molecule = methane ◦1 carbon bound to 4 H atoms ◦stable ◦a gas at room temperature

6. Hydrocarbons can grow adding C-C bonds ◦straight line  ethane  hexane ◦branching  isohexane ◦ring  cyclohexane 2003-2004 ethane hexane cyclohexane isohexane methane

7. Diversity of organic molecules 2003-2004

8. Isomers Molecules with same molecular formula but different structures ◦different chemical properties – C 6 H 14

9. Various kinds of isomers Molecules differ in structural arrangement of atoms Around a double bond – alkenes Isomers of ethene

10. Three of the four classes of macromolecules form chainlike molecules called polymers. ◦Polymers consist of many similar or identical building blocks linked by covalent bonds. The repeated units are small molecules called monomers. (like links of a chain) Most macromolecules are polymers

11. 4 MAIN MACROMOLECULES MOLECULE MONOMERUSES Proteins (amino acids) support/motion Lipids (glycerol & fatty acids) energy storage/insulation Carbohydrates (monosaccharides) quick energy Nucleic acids (nucleotides) store information They all contain CARBON and are called ORGANIC molecules (Also hydrogen, oxygen are in all of them)

12. Diversity of molecules Substitute other atoms or groups around the C ◦ethane vs. ethanol  H replaced by an hydroxyl group (–OH) ethanolethane What element is the blue one above? How many bonds does it form?

13. Hydroxyl –OH ◦organic compounds with OH = alcohols ◦names typically end in -ol  ethanol

14. More on Functional Groups 2003-2004

15. Types of functional groups 6 functional groups most important to chemistry of life: ◦hydroxyl amino ◦carbonyl sulfhydryl ◦carboxyl phosphate Affect reactivity ◦hydrophilic ◦increase solubility in water ◦Change all kinds of properties 2003-2004

16. Carboxyl –COOH ◦C double bonded to O & single bonded to OH group  compounds with COOH = acids ◦ fatty acids ◦ amino acids 2003-2004

17. Amino -NH 2 ◦N attached to 2 H  compounds with NH 2 = amines ◦ amnio acids  NH 2 acts as base ◦ ammonia picks up H + from solution 2003-2004

18. Viva la difference! Basic structure of male & female hormones is identical ◦identical C skeleton ◦attachment of different functional groups ◦interact with different targets in the body 2003-2004