Tetramethylammonium Hydroxide 25% Solution (TMAH)

Tetramethylammonium Hydroxide Solution, 25 wt.% in Water (TMAH) - 250 mL

SKU: 331635-250ML
106.00 Sale • Save

Item is in stock Only 0 left in stock Item is out of stock Item is unavailable

For laboratory, institutional, and professional use only. Not available for residential or personal purchase. Orders are subject to verification.

Adding to Cart Added to Cart

Tetramethylammonium hydroxide (TMAH) solution, 25 wt.% in water, is a strong organic base and quaternary ammonium compound widely used in organic synthesis, analytical chemistry, and semiconductor processing. * Laboratory address verification is required

This aqueous TMAH solution is commonly used as:

A strong base in organic reactions

A nucleophilic reagent

Anisotropic silicon etchant in microfabrication

pH adjustment reagent in advanced material synthesis

Catalyst and structure-directing agent in materials chemistry

With high alkalinity (pH >13 at 20 °C), this solution provides consistent base strength and reproducibility for research and industrial applications.

For laboratory and controlled-use environments only.

Chemical Name: Tetramethylammonium hydroxide
Synonyms: TMAH solution
CAS Number: 75-59-2
Linear Formula: (CH₃)₄N(OH)
Molecular Weight: 91.15 g/mol
Concentration: 25 wt.% in H₂O
Form: Liquid
Quality Level: 200
Functional Group: Amine (quaternary ammonium)
Primary Uses: Strong base, silicon etchant, pH adjustment

SPECIFICATIONS

Tetramethylammonium Hydroxide Solution, 25 wt.% in Water

Chemical Formula: (CH₃)₄N(OH)

CAS Number: 75-59-2

Molecular Weight: 91.15 g/mol

Concentration: 25 wt.% in H₂O

Form: Liquid

Quality Level: 200

Physical & Chemical Properties

pH: >13 (20 °C)

Density: 1.016 g/mL at 25 °C

Refractive Index: n20/D 1.3806

Vapor Pressure: 17.5 mmHg (20 °C)

Solubility: Water soluble

Chemical Identifiers

MDL Number: MFCD00008280

Beilstein/REAXYS Number: 3558708

PubChem Substance ID: 24859984

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

InChI Key: WGTYBPLFGIVFAS-UHFFFAOYSA-M

Storage Conditions

Store tightly closed

Protect from CO₂ absorption

Store at controlled room temperature

Bought together

You might also like

It's Our Responsibility

Small choices. Big impact.

Science moves us forward. So should sustainability. At Go Green Scientific, we offer carefully selected lab supplies designed to reduce waste and protect the planet—without compromising quality or compliance.

Science Meets Sustainability

We know scientists ask tough questions—and we welcome them. That’s why we vet every product for performance, sustainability, and integrity.