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| Names | |
|---|---|
| IUPAC name Ammonium ethanoate | |
| Identifiers | |
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3D model (JSmol) | |
| ChEBI | |
| ChemSpider |
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| ECHA InfoCard | 100.010.149 |
| EC Number |
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| RTECS number |
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| UNII | |
| UN number | 3077 |
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| Properties | |
| C2H7NO2 | |
| Molar mass | 77.083 g·mol−1 |
| Appearance | White solid crystals,deliquescent |
| Odor | Slightly acetic acid like |
| Density | 1.17 g/cm3 (20 °C)[1] 1.073 g/cm3 (25 °C) |
| Melting point | 113 °C (235 °F; 386 K)[4] |
| 102 g/100 mL (0 °C) 148 g/100 mL (4 °C)[1] 143 g/100 mL (20 °C) 533 g/100 mL (80 °C) | |
| Solubility | Soluble inalcohol,SO2,acetone, liquidammonia[2] |
| Solubility inmethanol | 7.89 g/100 mL (15 °C)[3][1] 131.24 g/100 g (94.2 °C)[2] |
| Solubility indimethylformamide | 0.1 g/100 g[2] |
| Acidity (pKa) | 9.9 |
| Basicity (pKb) | 33 |
| −41.1·10−6 cm3/mol | |
| Viscosity | 21 |
| Structure | |
| Orthorhombic | |
| Thermochemistry | |
Std enthalpy of formation(ΔfH⦵298) | −615 kJ/mol[2] |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards | Irritant |
| GHS labelling:[3] | |
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| Warning | |
| H303,H316,H320,H333 | |
| P281,P335 | |
| NFPA 704 (fire diamond) | |
| Flash point | 136 °C (277 °F; 409 K)[3] |
| Lethal dose or concentration (LD, LC): | |
LD50 (median dose) | 386 mg/kg (mice, intravenous)[2] |
| Safety data sheet (SDS) | JT Baker |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Ammonium acetate, also known asspirit of Mindererus inaqueous solution, is a chemical compound with the formula NH4CH3CO2. It is a white,hygroscopic solid and can be derived from the reaction ofammonia andacetic acid. It is available commercially.[5]
The synonym Spirit of Mindererus is named after R. Minderer, a physician fromAugsburg.[6]
It is the main precursor toacetamide:[7]
It is also used as a diuretic.[5]
As the salt of a weak acid and a weak base,ammoniumacetate is often used withacetic acid to create abuffer solution. Ammonium acetate isvolatile at low pressures. Because of this, it has been used to replace cell buffers that contain non-volatile salts in preparing samples for mass spectrometry.[8] It is also popular as a buffer for mobile phases forHPLC withELSD andCAD-based detection for this reason. Other volatile salts that have been used for this includeammonium formate.
When dissolving ammonium acetate in pure water, the resulting solution typically has a pH of 7, because the equal amounts of acetate and ammonium neutralize each other. However, ammonium acetate is a dual component buffer system, which buffers around pH 4.75 ± 1 (acetate) and pH 9.25 ± 1 (ammonium), but it has no significant buffer capacity at pH 7, contrary to common misconception.[9]
Ammonium acetate is also used as afood additive as an acidity regulator;INS number 264. It is approved for usage in Australia and New Zealand.[10]
Ammonium acetate is produced by the neutralization of acetic acid withammonium carbonate or by saturating glacialacetic acid withammonia.[11] Obtaining crystalline ammonium acetate is difficult on account of its hygroscopic nature.
