We begin our study of organic chemistry with the alkanes, compounds containing only two elements, carbon and hydrogen, and having only single bonds. There are several other kinds of hydrocarbons, distinguished by the types of bonding between carbon atoms and by the properties that result from that bonding. We will first examine hydrocarbons with double bonds, with triple bonds, and with a special kind of bonding called aromaticity. Then we will study some compounds considered to be derived from hydrocarbons by replacing one or more hydrogen atoms with an oxygen-containing group. Finally, we focuse on organic acids and bases, after which we will be ready to look at the chemistry of life itself—biochemistry—in the remaining five chapters. 11.0: Prelude to Organic Chemistry Hydrocarbons are the simplest organic compounds, but they have interesting physiological effects. These effects depend on the size of the hydrocarbon molecules and where on or in the body they are applied. Alkanes of low molar mass—those with from 1 to approximately 10 or so carbon atoms—are gases or light liquids that act as anesthetics. 11.1: Hydrocarbons The simplest organic compounds are hydrocarbons and are composed of carbon and hydrogen. Hydrocarbons can be aliphatic or aromatic; aliphatic hydrocarbons are divided into alkanes, alkenes, and alkynes. The combustion of hydrocarbons is a primary source of energy for our society. 11.2: Branched Hydrocarbons A unique name can be given to branched hydrocarbons. A unique structure can be drawn for the name of a hydrocarbon. 11.3: Alkyl Halides and Alcohols The presence of a halogen atom (F, Cl, Br, or I; X is also used to represent any halogen atom) is one of the simplest functional groups. Organic compounds that contain a halogen atom are called alkyl halides. 11.4: Other Oxygen-Containing Functional Groups Aldehydes, ketones, carboxylic acids, esters, and ethers have oxygen-containing functional groups. 11.5: Other Nitrogen and Sulfur-Containing Functional Groups There are some common, and important, functional groups that contain elements other than oxygen. In this section, we will consider three of them: amine, amide, and thiol functional groups. 11.6: Polymers Polymers are long molecules composed of chains of units called monomers. Several important biological polymers include proteins, starch, cellulose, and DNA. 11.E: Organic Chemistry (Exercises) These are exercises and select solutions to accompany Chapter 16 of the "Beginning Chemistry" Textmap formulated around the Ball et al. textbook. Template:HideTOC