Sodium acetate trihydrate, also known as sodium ethanoate is an odourless, white crystalline salt which is easily soluble in water. It is made from ethanoic acid and sodium carbonate or sodium hydroxide. It has many applications and is commonly used in the textile industries.
In the production of synthetic rubber. It helps to retard vulcanization of chloroprene.
As a pickling agent in Chrome tanning of animal skins in conjunction with chromium sulphate.
In the lab, as the conjugate base of a weak acid, a solution of sodium acetate and acetic acid can act as a buffer to keep a relatively constant pH. This is useful especially in biochemical applications where reactions are pH dependent. A formulation with ethanol may be used for precipitation of nucleic acids. It is often used in the preparation of gel stains for protein gel electrophoresis.
Sodium acetate is also used in consumer heating pads or hand warmers and is also used in “hot ice”. When sodium acetate trihydrate crystals (melting point 58 oC) are heated to around 100 oC, they melt. When this melt cools, it gives a supersaturated solution of sodium acetate in water. This solution is capable of supercooling to room temperature, well below its melting point, without forming crystals. By clicking on a metal disc in the heating pad, a nucleation center is formed which causes the solution to crystallize into solid sodium acetate trihydrate again. The bond-forming process of crystallization is exothermic, hence heat is emitted.
Not a hazardous substance or mixture according to Regulation (EC) No 1272/2008 This substance is not classified as dangerous according to Directive 67/548/EEC.