Dimethyl ether

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Dimethyl ether
Names
IUPAC name
Methoxymethane
Other names
Demeon
Dimethyl oxide
Dymel A
Mether
Methyl ether
Wood ether
Identifiers
Jmol-3D images Image
Properties
CH3OCH3
C2H6O
Molar mass 46.07 g/mol
Appearance Colorless gas
Odor Ether-like
Density 1.91855 g/cm3 (at 25°C)
Melting point −141 °C (−222 °F; 132 K)
Boiling point −24 °C (−11 °F; 249 K)
71 g/l (at 20 °C)
Solubility Soluble in acetone, chloroform, ethanol, methanol
Vapor pressure >100 kPa
Thermochemistry
−184.1 kJ·mol−1
Hazards
Safety data sheet Praxair
Flash point −41 °C
Related compounds
Related compounds
Diethyl ether
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Dimethyl ether or DME, also known as methoxymethane, is the organic compound with the formula CH3OCH3 (or C2H6O).

It is the simplest ether and an isomer of ethanol.

Properties

Chemical

Dimethyl ether is flammable and will burn when ignited in an oxygen atmosphere.

Dimethyl ether can be carbonylated to acetic acid:

CH3-O-CH3 + 2 CO + H2O → 2 CH3-COOH

This reaction proceeds under high pressure.

Physical

Dimethyl ether is a colorless gas at standard conditions, with an ethereal smell. It melts at −141 °C and boils at −24 °C. DME is poorly soluble in water (71 g/l at standard conditions), but soluble in most organic solvents, such as acetone, chloroform, ethanol, methanol.

Availability

Dimethyl ether is available in some type of wart remover sprays, usually mixed with propane.

Some car starter fluids also contain dimethyl ether.

MAP-plus blowtorch gas blends may contain DME.

Preparation

Dimethyl ether can be prepared by dehydration of methanol, in the presence of a catalyst, such as conc. sulfuric acid. The resulting gaseous dimethyl ether is dried and either dissolved in a solvent or compressed in a gas tube.

Projects

Handling

Safety

Dimethyl ether is a flammable gas. It poses relative low toxicity.

Storage

In gas cylinders, which should be kept in cool and dark places, away from light and heat.

Unlike most common ethers, dimethyl ether does not form peroxides upon exposure to air. Therefor, DME solutions do not require antioxidants.

Disposal

DME can be safely burned or released in open air. It poses little threat to the environment.

References

Relevant Sciencemadness threads