Sodium formate
| Names | |
|---|---|
| IUPAC name
Sodium formate
| |
| Other names
Formic acid, sodium salt
| |
| Properties | |
| HCOONa | |
| Molar mass | 68.007 g/mol |
| Appearance | White hygroscopic solid |
| Odor | Odorless |
| Density | 1.92 g/cm3 (20 °C) |
| Melting point | 253 °C (487 °F; 526 K) |
| Boiling point | Decomposes |
| 43.82 g/100 mL (0 °C) 97.2 g/100 mL (20 °C) 160 g/100 mL (100 °C) | |
| Solubility | Soluble in ethanol, formic acid, methanol Slightly soluble in glycerol Insoluble in diethyl ether, toluene |
| Vapor pressure | ~0 mmHg |
| Acidity (pKa) | 7.0-8.5 (0.1 M) |
| Thermochemistry | |
| Std molar
entropy (S |
103.8 J·mol−1·K−1 |
| Std enthalpy of
formation (ΔfH |
-666.5 kJ/mol |
| Hazards | |
| Safety data sheet | FischerScintific |
| Flash point | Non-flammable |
| Related compounds | |
| Related compounds
|
Calcium formate |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Sodium formate is the sodium salt of formic acid, with the chemical formula HCOONa or HCO2Na.
Contents
Properties
Chemical
Adding a strong acid, like sulfuric acid will give sodium sulfate and formic acid.
- 2 HCOONa + H2SO4 → 2 HCOOH + Na2SO4
If the acid is too concentrated, carbon monoxide will evolve.
- 2 HCOONa + H2SO4 → Na2SO4 + 2 H2O + CO + CO2
Physical
Sodium formate is a hygroscopic colorless salt, soluble in water and formic acid. It decomposes when heated above 253°C.
Availability
Some commercial deicers are ~90% sodium formate.
Lastly it can be purchased from chemical suppliers.
Preparation
There are several routes to formic acid.
The simplest way is to slowly add sodium bicarbonate to a concentrated solution of formic acid.
- NaHCO3 + HCOOH → HCOONa + H2O + CO2
The solution is then cooled to precipitate the sodium formate which is filtered and dried.
The haloform reaction of ethanol/acetaldehyde and sodium hypochlorite will yield chloroform and sodium formate.
Projects
- Make formic acid
- Make ethyl formate
Handling
Safety
Sodium formate is irritant and should be handled with proper protection. Contact with strong acids should be avoided as it will generate formic acid and carbon monoxide.
Storage
Sodium formate should be stored in closed bottles, away from acids.
Disposal
Heating it in a kiln will cause it to break down into sodium carbonate, carbon monoxide and water vapor.
