Ammonium acetate

Ammonium acetate
Ammonium acetate
Identifiers
CAS number 631-61-8 YesY
ChemSpider 11925 YesY
UNII RRE756S6Q2 YesY
RTECS number AF3675000
Jmol-3D images Image 1
Properties
Molecular formula C2H3O2NH4
Molar mass 77.0825 g/mol
Appearance white solid crystals
deliquescent
Density 1.17 g/cm3[1]
Melting point

114 °C, 387 K, 237 °F

Boiling point

decomposes

Solubility in water 148 g/100 ml (4 °C)
Solubility in methanol 7.89 g/100 mL (15 °C)
Structure
Crystal structure orthorhombic
Hazards
MSDS JT Baker
GHS pictograms GHS-pictogram-exclam.svg[2]
GHS hazard statements H315, H319, H335[2]
GHS precautionary statements P261, P305+351+338[2]
NFPA 704
NFPA 704.svg
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Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Ammonium acetate is a chemical compound with the formula CH3COONH4 (or C2H4O2.NH3 or C2H7NO2). It is a white solid, which can be derived from the reaction of ammonia and acetic acid. It is available commercially and, depending on grade, can be rather inexpensive.

Contents

Uses and distinctive properties

Ammonium acetate

As the salt of a weak acid and a weak base, ammonium acetate has a number of distinctive properties.

  • NH4C2H3O2 is occasionally employed as a biodegradable de-icing agent.
  • It is often used with acetic acid to create a buffer solution, one that can be thermally decomposed to non-ionic products
  • Ammonium acetate is useful in the Knoevenagel condensation in organic synthesis.
  • It is a relatively unusual example of a salt that melts at low temperatures.
  • Can be used with distilled water to make a protein precipitating reagent.
  • Is often used as an aqueous buffer for ESI mass spectrometry of proteins and other molecules.

Ammonium acetate is volatile at low pressures. Because of this it has been used to replace cell buffers with non-volatile salts, in preparing samples for mass spectrometry. [3] It is also popular as a buffer for mobile phases for HPLC with ELSD detection for this reason. Other volatile salts which have been used for this include ammonium formate.

Food Additive

Ammonium acetate is also used as a food additive as an acidity regulator; INS number 264. It is approved for usage in Australia and New Zealand.[4]

Properties

CH3COONH4 is hygroscopic. It decomposes easily at elevated temperatures into acetamide.

CH3COONH4 → CH3C(O)NH2 + H2O

In this reaction, a salt is converted to two molecular species, which is a relatively uncommon conversion at mild temperatures.

References

  1. ^ Pradyot Patnaik. Handbook of Inorganic Chemicals. McGraw-Hill, 2002, ISBN 0-07-049439-8
  2. ^ a b c Online Sigma Catalogue , accessdate: June 8, 2011.
  3. ^ Berman et al., 2008. J Am Soc Mass Spectrom, 19:1230-1236.
  4. ^ Australia New Zealand Food Standards Code"Standard 1.2.4 - Labelling of ingredients". http://www.comlaw.gov.au/Details/F2011C00827. Retrieved 2011-10-27. 

Further reading

  • G. Jones, Organic Reactions, 1967, volume 15, 204ff (the Knoevenagel Reaction)

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Look at other dictionaries:

  • ammonium acetate — noun The ammonium salt of acetic acid, CHCONH, that is used as a buffer in standard electrodes …   Wiktionary

  • ammonium acetate — Chem. a white, crystalline, deliquescent, water soluble solid, NH4(C2H3O2), used chiefly in the manufacture of dyes and meat preservatives. * * * …   Universalium

  • ammonium acetate — Chem. a white, crystalline, deliquescent, water soluble solid, NH4(C2H3O2), used chiefly in the manufacture of dyes and meat preservatives …   Useful english dictionary

  • Acétate d'ammonium — Général Nom IUPAC Acétate d ammonium No CAS …   Wikipédia en Français

  • Acetate — For other uses, see Acetate (disambiguation). acetate anion …   Wikipedia

  • acétate — [ asetat ] n. m. • 1787; de acét(ique) et suff. chim. ate ♦ Chim. Sel ou ester de l acide acétique. Acétate cuivrique (verdet). Acétate d aluminium, employé comme mordant. Acétate de cellulose, ou absolt acétate, employé dans la fabrication de… …   Encyclopédie Universelle

  • Thiocyanate d'ammonium —   Général …   Wikipédia en Français

  • Chlorure d'ammonium — Général Nom IUPAC Chlorure d ammonium No CAS …   Wikipédia en Français

  • 631-61-8 — Acétate d ammonium Acétate d ammonium Général No CAS …   Wikipédia en Français

  • C2H7NO2 — Acétate d ammonium Acétate d ammonium Général No CAS …   Wikipédia en Français

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