Draw the structure of sodium stearate. Determine if this is soap.
The correct answer and explanation is :
The image above shows the structure of sodium stearate. It consists of a long-chain fatty acid salt with a carboxylate group (-COO-) attached to a sodium ion (Na). The hydrocarbon chain has 18 carbon atoms, and the carboxylate group is bonded to the sodium ion.
Is Sodium Stearate Soap?
Yes, sodium stearate is a type of soap. It is formed by the reaction between stearic acid (a fatty acid) and sodium hydroxide (NaOH), in a process known as saponification. The result is a salt of the fatty acid (sodium stearate), which has soap-like properties.
The carboxylate group in sodium stearate interacts with water molecules, allowing it to form micelles, which help trap and remove dirt, oil, and grease. The hydrophobic (water-repelling) tail of the fatty acid chain binds to oils, while the hydrophilic (water-attracting) head interacts with water, aiding in cleaning. This characteristic makes sodium stearate an effective cleansing agent, widely used in soap production.
Sodium stearate’s ability to emulsify oils and its solubility in water makes it an essential ingredient in various cleaning products, including soaps, body washes, and shampoos. Therefore, it qualifies as soap, as it is derived from fatty acids and has surfactant properties, typical of soap molecules.