Chapter 9 Carbon Chemistry

I. Simple Organic Compounds A. Organic Compounds All living things on Earth are made of carbon-containing compounds Carbon can from four covalent bonds because it has four valence electrons Carbon frequently combines with hydrogen atoms

B. Hydrocarbons A compound that contains only carbon and hydrogen Examples: - Methane (natural gas, CH4) - Ethane (C2H6)

C. Saturated Hydrocarbons Carbon and hydrogen atoms are joined by single covalent bonds No additional hydrogens can be added to the molecule The carbon atoms are saturated with hydrogen atoms

Short hydrocarbon chains have low boiling points - Make good fuels Longer hydrocarbon chains are found in oils Saturated hydrocarbons are named with an -ane ending Compounds are known as alkanes

D. Unsaturated Hydrocarbons Some carbon and hydrogens in a chain are bound by double and triple bonds Carbon atoms are not saturated with hydrogens Hydrocarbons with at least one double bond are named with an –ene ending These compounds are called alkenes

E. Triple Bonds Three pairs of electrons are bonded together Compounds are called alkynes Named with an –yne ending

F. Hydrocarbon Isomers Atoms in an organic molecule can have different arrangements but still have the same molecular formula - Known as isomers

These compounds have different chemical and physical properties because of their different structures As the size of a hydrocarbon molecule increases, the number of possible isomers also increases

G. Hydrocarbons in Rings Some hydrocarbons can bond in a ring form The prefix cyclo- tells you the molecules are cyclic Can contain one or more double bonds Examples: sucrose, glucose, and fructose

II. Other Organic Compounds A. Substituted Hydrocarbons One or more hydrogen atoms are replaced by other atoms or groups of atoms Result in compounds with different chemical properties

B. Alcohols A hydroxyl group (-OH) can be added to a hydrocarbon Forms an alcohol

C. Carboxylic Acid A carboxyl group consists of a carbon atom with a double bond with one oxygen and a single bond with a hydroxyl (-OH) group - it’s formula is -COOH A carboxyl group when substituting a hydrogen, forms a carboxylic acid

D. Amines An amino group is a nitrogen joined to two hydrogens - Its formula is –NH2 Apart of may biological compounds that are essential for life When an amino group bonds with one more hydrogen, the result is ammonia, NH3

E. Amino Acids Forms when an amino group (-NH2) and a carboxyl group (-COOH) replaces hydrogens on the same carbon

F. The Building Block of Protein Amino acids build proteins Twenty different amino acids bond in different combinations to form a variety of proteins Most amino acids are nonessential because they are made within the human body Nine amino acids are essential, meaning they need to be consumed by eating protein-rich foods

III. Biological Compounds A. Polymers A molecule made up of many small organic molecules linked together with covalent bonds to form a long chain Small organic molecules that are linked together are called monomers Bound together in a chemical reaction called polymerization

Synthetic polymers can be made in the laboratory - plastics, synthetic fibers, nonstick surface cookware

B. Proteins Proteins are natural polymers made in your body Proteins in the form of enzymes speed up chemical reactions Some proteins make up structural materials - ligaments, tendons, muscles, cartilage, hair, and fingernails The protein, hemoglobin, carries oxygen through blood

C. Carbohydrates An organic compound that contains carbon, hydrogen, and oxygen - Usually in a ratio 1C:2H:1O Carbohydrates are broken down into simple sugars that the body can use for energy

1. Sugars Contain five, six, or seven carbon atoms arranged in a ring Glucose is found in many naturally sweet foods Fructose is found in sweeteners Sucrose is in table sugar

2. Starches Large carbohydrates i.e. rice, wheat, corn, potatoes Polymers of glucose Sources of large amounts of energy

3. Other glucose polymers Cellulose makes up stiff fibers found in the walls of plant cells The human digestive system cannot convert cellulose into sugars

D. Lipids Contains carbon, hydrogen, and oxygen in different proportions Commonly called fats and oils

1. Lipids Store Energy Excess energy in your body are stored by producing lipids Energy is absorbed in a lipid by an endothermic reaction Energy is released from a lipid by an exothermic reaction Large amounts of lipids are stored as fat on your body

2. Saturated and Unsaturated Lipids When the lipid is saturated with hydrogens, the chains are straight because all the bonds are single bonds They are able to pack together, forming a solid

When a lipid is unsaturated, the molecule bends wherever there is a double bond They are prevented from packing together and tend to be liquid at room temperature

E. Cholesterol A complex lipid that is present in foods that is not a fat Needed for making cell membranes