Cas Number


Other Names

E211, benzoate of soda

The formula



Sodium benzoate is a substance which has the chemical formula NaC7H5O2. It is a widely used food preservative, with an E number of E211. It is the sodium salt of benzoic acid and exists in this form when dissolved in water. It can be produced by reacting sodium hydroxide with benzoic acid.

Physical and Chemical Properties
Physical state and Appearance : Solid. (Granular solid. crystalline powder.)
Odor : Odorless.
Molecular Weight : 144.11 g/mole
Color : White.
Melting Point : >300 °C (572 °F)
Vapor Density : 4.97 (Air = 1)
Solubility : Easily soluble in cold water, hot water
Content, % : 99.0 min.
Loss on Drying, % : 2
The Acid & Alkalinity : ≤ 0.2ml
Chlorides : ≤ 0.02
Total Chlorine : ≤ 0.03
Heavy Metal : ≤ 0.001
Arsenic : ≤ 00003
Mercury : ≤ 0.00001

Used food preservative and soft drink products.

It is also used in personal care products like toothpaste, dentifrice cleaners, and mouthwashes.

It is used as an intermediate during the manufacture of dyes.

It is an antiseptic medicine and a rust and mildew inhibitor.

It is also used in tobacco and pharmaceutical preparations.

It is used as a fungicide.

A relatively recent use for sodium benzoate is as a corrosion inhibitor in engine coolant systems.

Sodium benzoate has recently been incorporated into plastics, like polypropylene, where it has been found to improve clarity and strength.