Tetramethylammonium hydroxide

Tetramethylammonium hydroxide
Names
IUPAC name
N,N,N-Trimethylmethanaminium hydroxide
Other names
tetramethylammonium hydroxide
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.000.803 Edit this at Wikidata
UNII
  • InChI=1S/C4H12N.H2O/c1-5(2,3)4;/h1-4H3;1H2/q+1;/p-1 checkY
    Key: WGTYBPLFGIVFAS-UHFFFAOYSA-M checkY
  • InChI=1/C4H12N.H2O/c1-5(2,3)4;/h1-4H3;1H2/q+1;/p-1
    Key: WGTYBPLFGIVFAS-REWHXWOFAQ
  • C[N+](C)(C)C.[OH-]
Properties
C4H13NO
Molar mass 91.154 g·mol−1
Density ~ 1.015 g/cm3 (20-25% aqueous solution)
Melting point 67 °C (153 °F; 340 K) (pentahydrate)
Boiling point decomposes
high
Hazards
GHS labelling:
GHS05: Corrosive GHS06: Toxic

[1]

Danger[1]
H300, H311, H314[1]
P260, P264, P270, P280, P301+P310, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P322, P361, P363, P405, P501[1]
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
0
0
Safety data sheet (SDS) Sigma-Aldrich MSDS for TMAH·5H2O
Related compounds
Other anions
tetramethylammonium chloride
Other cations
tetraethylammonium hydroxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Tetramethylammonium hydroxide (TMAH or TMAOH) is a quaternary ammonium salt with molecular formula N(CH3)4+ OH. It is commonly encountered in form of concentrated solutions in water or methanol. TMAH in solid state and its aqueous solutions are all colorless, but may be yellowish if impure. Although TMAH has virtually no odor when pure, samples often have a strong fishy smell due to presence of trimethylamine which is a common impurity. TMAH has several diverse industrial and research applications.