Sodium acetate or sodium ethanoate is the sodium salt of acetic acid and its chemical formula is C2H3O2Na. Sodium acetate is a cheap chemical with a wide range of uses. Sodium acetate may be found as an anhydrous salt or a trihydrate. Sodium acetate is an ionic compound that has all of the common physical properties of ionic substances.
Sodium acetate can be produced industrially by reacting large amounts of glacial acetic acid with sodium hydroxide, as seen in the following reaction.
C2H4O2 + NaOH → NaO2CCH3 + H2O
Sodium acetate is used as a food additive and added to food to help prevent bacterial growth. Sodium acetate can be used as a neutralizer for basic or alkaline foods, but also as a buffer to help maintain a specific pH. Sodium acetate can also be used to enhance flavor and there are no known adverse effects on human health. Sodium acetate is used as a seasoning in the food industry for the flavor of salt and vinegar.
A flat, uneven, metal disc is placed in solution. A small amount of sodium acetate crystals is released when the disk is moved. These crystals start a chain reaction of crystallization with the rest of the sodium acetate. This reaction is instantaneous, releasing a lot of energy stored in the sodium acetate crystal structure. The crystallization of sodium acetate is exothermic. This principle is used in heating pads. The heating pad is reusable since sodium acetate can return back to supersaturated liquid state when it is placed in boiling water and then allowed to cool to room temperature.
Sodium acetate neutralizes the sulphuric acid found in waste streams from textile industries. It is also used as a photoresist when aniline dyes are used. In the rubber industry it delays vulcanization of chloroprene in synthetic rubber. It acts as a sealant in concrete and lessens water permeation to prevent damage. It also helps in the removal of stains, rust and other impurities from metallic surfaces.