- N,N,N-Trimethylmethanaminium hydroxide
Tetramethylammonium hydroxide is a solid in the hydrated form or a colorless liquid with a strong ammonia-like odor.
Registry Numbers and Inventories.
R 10 23/25 35 51
S 7 26 36/37/39 45
Japan ENCS (MITI)
Vapor pressure, mmHg
18 (25 C)
Vapor density (air=1)
0.4 (butyl acetate=1)
1.016 g/cm3 (25 C)
Solubility in water
1.38 (20 C)
Hazards and Protection.
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Wear appropriate protective gloves, clothing and goggles.
Wear positive pressure self-contained breathing apparatus (SCBA).
Keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary.
Avoid contact with strong acids and oxidizing agents. Attacks many plastics and rubber. May react with metallic aluminum and generate hydrogen gas.
Above the flash point, explosive vapor-air mixtures may be formed.
Upper exp. limit, %
Lower exp. limit, %
Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Solid streams of water may be ineffective. Use alcohol foam, dry chemical or carbon dioxide.
May burn but does not ignite readily.
When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. May polymerize explosively when heated or involved in a fire. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form.
Fire may produce irritating, corrosive and/or toxic gases.
TOXIC; inhalation, ingestion, or skin contact with material may cause severe injury or death. Effects of contact or inhalation may be delayed.
Contact with molten substance may cause severe burns to skin and eyes. See Inhalation.
Seek medical assistance.
Move victim to fresh air. Apply artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; induce artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult.
Remove and isolate contaminated clothing and shoes. Immediately flush with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin.
Immediately flush with running water for at least 20 minutes.