Essay About Carboxylic Acid And Derivativesa Carboxyl Group

Carboxylic Acid and Its Derivatives
GROUP 4                                                                        FEBRUARY 23, 2015PHARM-1A                                                                        RATING:EXPERIMENT 9CARBOXYLIC ACID AND ITS DERIVATIVESA carboxyl group (COOH) is a functional group consisting of a carbonyl group (C=O) with a hydroxyl group (O-H) attached to the same carbon atom. Carboxyl groups have the formula -C(=O)OH, usually written as -COOH or CO2H. Carboxylic acids are a class of molecules which are characterized by the presence of one carboxyl group. As proton donors, carboxylic acids are characterized as Brønsted-Lowry acids. Acids with two or more carboxylic groups are called dicarboxylic, tricarboxylic, etc. Salts and esters of carboxylic acids are called carboxylates. Carboxylate ions are resonance-stabilized. This increased stability leads to increased acidity compared to that of alcohols. Carboxylic acids act as both hydrogen bond acceptors, due to the carbonyl group, and hydrogen bond donors, due to the hydroxyl group. As a result, they often participate in hydrogen bonding. Carboxylic acids usually exist as dimeric pairs in nonpolar media because of their tendency to “self-associate.” This tendency to hydrogen bond gives them increased stability as well as higher boiling points relative to the acid in aqueous solution. Carboxylic acids are polar molecules; they tend to be soluble in water, but as the alkyl chain gets longer, their solubility decreases due to the increasing hydrophobic nature of the carbon chain. Carboxylic acids are characterized as weak acids, meaning that they do not fully dissociate to produce H+cations in a neutral aqueous solution.DATA ANALYSISOBSERVATIONESTERIFICATIONWhen ethanol and acetic acid solution was added with concentrated H2SO4, the solution produced heat. It has an unpleasant smell. When it was warmed in the water, both the unpleasant smell of the solution was concealed when NaOH was added.FeCl3With HCl: When NaOH and acetic acid solution was added with FeCl3, the solution turned red. And when added with HCl the solution slowly turned yellow.Without HCl: When NaOH and acetic acid solution was added with FeCl3 the solution turned red.Acetic anhydrideWhen water was added with acetic acid anhydride the solution produced heat(above room temperature) and it has an unpleasant odor.BenzamideIt has a strong smell like an old shoebox, then the blue litmus paper turned red therefore it is an acid.OxalateThe stain was removed from the cloth.A. ESTERIFICATION