stearic+acid


 * Stearic acid** (first syllable pronounced either //steer// or //stair//) is the saturated fatty acid with an 18 carbon chain and has the IUPAC name **octadecanoic acid**. It is a waxy solid, and its chemical formula is CH3(CH2)16CO2H. Its name comes from the Greek word στέαρ //"stéar"//, which means tallow. The salts and esters of stearic acid are called **stearates**. Stearic acid is noteworthy as the most common saturated fatty acid, another common one being the C16 compound palmitic acid.Generally applications of stearic acid exploit its bifunctional character, with a polar head group that can be attached to metal cations and a nonpolar chain that confers solubility in organic solvents. The combination leads to uses as a surfactant and softening agent. Stearic acid undergoes the typical reactions of saturated carboxylic acids, notably reduction to stearyl alcohol, and esterification with a range of alcohols.