Sodium benzoate from the store.
| IUPAC name
| Other names
Benzoate of soda
|Molar mass||144.10 g/mol|
|Melting point||410 °C (770 °F; 683 K) (decomposes)|
| 62.69 g/100 ml (0 °C)|
62.78 g/100 ml (15 °C)
62.81 g/100 ml (20 °C)
62.87 g/100 ml (30 °C)
71.11 g/100 ml (100 °C)
|Solubility||Soluble in liq. ammonia, pyridine|
|Solubility in 1,4-Dioxane||0.0000818 g/100 g (25 °C)|
|Solubility in ethanol|| 2.3 g/100 g (25 °C)|
8.3 g/100 g (78 °C)
|Solubility in methanol|| 8.22 g/100 g (15 °C)|
7.55 g/100 g (66.2 °C)
|Vapor pressure||2.9·10-12 mmHg (25 °C)|
|Safety data sheet||Sigma-Aldrich|
|Flash point||100 °C (212 °F; 373 K)|
|Lethal dose or concentration (LD, LC):|
LD50 (Median dose)
|4,100 mg/kg (rat, oral)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Sodium benzoate is an organic chemical compound, used as a food preservative.
- C6H5COONa + NaOH → C6H6 + Na2CO3
Small amounts of biphenyl and benzophenone will also be produced as side products.
Ascorbic acid will also reduce the salt to benzene under certain conditions.
Sodium benzoate is a white hygroscopic compound, with a characteristic smell. It has a solubility in water of 62.7 g/100 ml at standard conditions. Sodium benzoate is also soluble in liquid ammonia and pyridine. It is poorly soluble in most alcohols, like methanol and ethanol.
Sodium benzoate is available as a food preservative, sold in sealed bags.
Sodium benzoate can be prepared by reacting benzoic acid and sodium hydroxide, bicarbonate or carbonate.
Sodium benzoate has low toxicity to humans, and recent studies have shown to have some beneficial effects, in preventing Alzheimer and Parkinson's, though the results aren't conclusive so far. Cats however, have a significantly lower tolerance against benzoic acid and its salts, than rats and mice.
If consumed with ascorbic acid, it may yield benzene, which is carcinogen, phenomenon observed in drinks containing sodium benzoate as preservative. However the levels of benzene obtained are extremely small, and studies have shown that the concentration of benzene is well below the safety limit.
Sodium benzoate should be stored in closed bottles, as it's slightly hygroscopic, though keeping it in a dry chamber is sufficient.
Sodium benzoate has low toxicity and doesn't require special disposal. Discard it as you wish.