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334901

Sigma-Aldrich

Tetramethylammonium hydroxide solution

25 wt. % in methanol

Synonym(s):
N,N,N-trimethyl-methanaminium hydroxide, TMAH, TMAOH
Linear Formula:
(CH3)4N(OH)
CAS Number:
Molecular Weight:
91.15
Beilstein:
3558708
MDL number:
PubChem Substance ID:

vapor pressure

17.5 mmHg ( 20 °C)

Quality Level

form

liquid

concentration

25 wt. % in methanol

impurities

≤10% water
≤2% chloride

density

0.866 g/mL at 25 °C

SMILES string

[OH-].C[N+](C)(C)C

InChI

1S/C4H12N.H2O/c1-5(2,3)4;/h1-4H3;1H2/q+1;/p-1

InChI key

WGTYBPLFGIVFAS-UHFFFAOYSA-M

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1 of 4

This Item
32825186631B32602
form

liquid

form

-

form

liquid

form

liquid

concentration

25 wt. % in methanol

concentration

10 wt. % in H2O

concentration

~25% in methanol (~1.5 M)

concentration

40 wt. % in methanol

impurities

≤10% water, ≤2% chloride

impurities

-

impurities

-

impurities

-

density

0.866 g/mL at 25 °C

density

1.006 g/mL at 25 °C

density

-

density

0.92 g/mL at 25 °C

Quality Level

200

Quality Level

100

Quality Level

100

Quality Level

200

General description

Tetramethylammonium hydroxide is a quaternary ammonium salt generally used as an anisotropic etchant for silicon due to its high silicon etching rate.

Application

Tetramethylammonium hydroxide solution (25 wt.% solution in methanol) may be used in the synthesis of zirconium oxides via a modified sol-gel method with potential application as catalyst materials in CO hydrogenation.

Signal Word

Danger

Hazard Classifications

Acute Tox. 2 Dermal - Acute Tox. 2 Oral - Acute Tox. 3 Inhalation - Aquatic Chronic 3 - Eye Dam. 1 - Flam. Liq. 3 - Skin Corr. 1B - STOT RE 1 Dermal - STOT SE 1

Storage Class Code

3 - Flammable liquids

WGK

WGK 2

Flash Point(F)

80.6 °F - closed cup

Flash Point(C)

27 °C - closed cup

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

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The Mars Curiosity rover carries a diverse instrument payload to characterize habitable environments in the sedimentary layers of Aeolis Mons. One of these instruments is Sample Analysis at Mars (SAM), which contains a mass spectrometer that is capable of detecting
Characterization of Zirconia-based catalysts prepared by precipitation, calcination, and modified sol-gel methods.
Feng Z, et al.
Industrial & Engineering Chemistry Research, 34(1), 78-82 (1995)
Study on anisotropic silicon etching characteristics in various surfactant-added tetramethyl ammonium hydroxide water solutions.
Yang CR, et al.
Journal of Micromechanics and Microengineering, 15(11), 2028-2028 (2005)
The characteristic behavior of TMAH water solution for anisotropic etching on both silicon substrate and SiO 2 layer.
Chen PH, et al.
Sensors and actuators A, Physical, 93(2), 132-137 (2001)
Xosé López-Goldar et al.
PloS one, 15(5), e0232692-e0232692 (2020-05-02)
Inducibility of defences in response to biotic stimuli is considered an important trait in plant resistance. In conifers, previous research has mostly focused on the inducibility of the volatile fraction of the oleoresin (mono- and sesquiterpenes), leaving the inducibility of

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