LECTURE 13 Friday 22417 Chapter 15 Carboxylic Acids

LECTURE 13 Friday 2/24/17

Chapter 15 Carboxylic Acids and Esters

CARBOXYLIC ACIDS • The functional group of • Many carboxylic acids have common names.

CARBOXYLIC ACID EXAMPLES

CARBOXYLIC ACID EXAMPLES

• ________ are carboxylic acids with long hydrocarbon chains, generally • They were first isolated from natural fats. • These fats are known almost exclusively by their common names.

CARBOXYLIC ACIDS IUPAC NOMENCLATURE • Find the longest carbon chain that contains the –COOH group. • Drop the –e from the end of the hydrocarbon name and substitute –oic acid. • Number the longest chain. Carbon number 1 is the carboxyl carbon. • Name and number other attached groups. • Examples:

CARBOXYLIC ACIDS IUPAC NOMENCLATURE (continued) • Aromatic acid names are derived from the parent compound, benzoic acid. • Example:

PHYSICAL PROPERTIES OF CARBOXYLIC ACIDS • Low molecular weight carboxylic acids are ______ at room temperature and have characteristically sharp or unpleasant odors. • The –COOH group • Hydrogen bonding between –COOH groups creates • This gives carboxylic acids

PHYSICAL PROPERTIES OF CARBOXYLIC ACIDS (continued)

PHYSICAL PROPERTIES OF CARBOXYLIC ACIDS (continued)

PHYSICAL PROPERTIES OF CARBOXYLIC ACIDS (continued) • –COOH groups can hydrogen bond with water.

PHYSICAL PROPERTIES OF CARBOXYLIC ACIDS (continued)

ACIDITY OF CARBOXYLIC ACIDS • Carboxylic acids behave as weak acids (low dissociation), forming • Example:

SALTS OF CARBOXYLIC ACIDS • Carboxylic acids react readily with strong bases (Na. OH, KOH) to form salts.

SALTS OF CARBOXYLIC ACIDS (continued) • Examples:

SALTS OF CARBOXYLIC ACIDS (continued) • To name a carboxylic acid salt, name the metal ion first and change the –ic ending of the acid name to –ate. • Example:

SALTS OF CARBOXYLIC ACIDS (continued) • Carboxylic acid salts are solids at room temperature. • They are usually soluble in water because they are ionic.

USEFUL CARBOXYLIC ACID SALTS • Na+ and K+ salts of long-chain acids are used • Calcium and sodium propanoate are used as ______ in bakery products. • Sodium benzoate is a food _______ used in ketchup and soda pop. • Zinc 10 -undecylenate is used____________

USEFUL CARBOXYLIC ACID SALTS (continued) • A mixture of sodium citrate and citric acid is widely used as a buffer to control p. H. • The buffer can be found in: