While your hardworking brains are not quite ready to take organic chemistry yet, simple organic compounds show up quite regularly in Chem 101 and 102. In this lesson, I'll quickly point out three of the most common classes of organic molecules, the alkanes, alcohols, and carboxylic acids. alkanes are a type of hydrocarbon, meaning that they are formed of only carbon and hydrogen atoms. The structure of an alkane contains two hydrogen atoms for every carbon atom, plus two more hydrogen atoms at the end, sort of like if a dinner table were a string of carbon atoms and the chairs were hydrogen. Some alkanes form a ring structure we call those cyclow alkanes. Alkanes all end inane and have different prefixes depending on how many carbon atoms they have. Cyclow alkanes include the prefix cyclow. When an organic compound contains an OH group that is an oxygen bonded to a hydrogen, we call that compound an alcohol. Small alcohols mix very easily with water, such as ethyl alcohol, also known as drinking alcohol. Another common organic group is the carboxylic acid. A carboxylic acid has a carbon that forms bonds to two oxygen atoms. One of the oxygen atoms has a spicy hydrogen, which gives this the properties of an acid. To indicate a carboxylic acid, we use COOH in the molecular formula.