Sodium formate

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Sodium formate
Structural formula of sodium formate
Ball-and-stick model of the formate anion The sodium cation
Identifiers
CAS number 141-53-7 YesY
PubChem 2723810
ChemSpider 8517 YesY
UNII 387AD98770 YesY
EC number 205-488-0
ChEMBL CHEMBL183491 N
Jmol-3D images Image 1
Properties
Molecular formula HCOONa
Molar mass 68.007 g/mol
Appearance white granules
deliquescent
Density 1.92 g/cm3 (20 °C)
Melting point 253 °C (487 °F; 526 K)
Boiling point decomposes
Solubility in water 43.82 g/100 mL (0 °C)
97.2 g/100 mL (20 °C)
160 g/100 mL (100 °C)
Solubility insoluble in ether
soluble in glycerol, alcohol, formic acid
Acidity (pKa) 7.0-8.5 (0.1M)
Thermochemistry
Specific
heat capacity
C
82.7 J/mol K
Std molar
entropy
So298
103.8 J/mol K
Std enthalpy of
formation
ΔfHo298
-666.5 kJ/mol
Gibbs free energy ΔG -599.9 kJ/mol
Hazards
EU classification not listed
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentine Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 N (verify) (what is: YesY/N?)
Infobox references

Sodium formate, HCOONa, is the sodium salt of formic acid, HCOOH. It usually appears as a white deliquescent powder.

Uses[edit]

Sodium formate is used in several fabric dyeing and printing processes. It is also used as a buffering agent for strong mineral acids to increase their pH, as a food additive (E237), and as a de-iceing agent.

Preparation[edit]

Sodium formate can be prepared in the laboratory by neutralizing formic acid with sodium carbonate. It can also be obtained by reacting chloroform with an alcoholic solution of sodium hydroxide.

CHCl3 + 4NaOH → HCOONa + 3NaCl + 2H2O

or by reacting sodium hydroxide with chloral hydrate.

C2HCl3(OH)2 + NaOHCHCl3 + HCOONa + H2O

The latter method is, in general, preferred to the former because the low aqueous solubility of CHCl3 makes it easier to separate out from the sodium formate solution, by fractional crystallization, than the soluble NaCl would be.

For commercial use, sodium formate is produced by absorbing carbon monoxide under pressure in solid sodium hydroxide at 160 °C.

CO + NaOH → HCOONa

Sodium formate may also be created via the haloform reaction between ethanol and sodium hypochlorite in the presence of a base. This procedure is well documented for the preparation of chloroform.

See also[edit]

References[edit]