Sodium amide

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Sodium amide
Names
IUPAC names
Sodium amide
Sodium azamide
Other names
Sodamide
Properties
NaNH2
Molar mass 39.01 g/mol
Appearance White or grayish solid
Odor Odorless
Ammonia-like (in moist air)
Density 1.39 g/cm3 (20 °C)
Melting point 210 °C (410 °F; 483 K)
Boiling point 400 °C (752 °F; 673 K)
Reacts
Solubility Reacts with alcohols, carboxylic acids
Solubility in ammonia 0.004 g/100 ml
Acidity (pKa) 38
Thermochemistry
76.9 J·mol-1·K-1
-118.8 kJ/mol
Hazards
Safety data sheet Sigma-Aldrich
Flash point 4.44 °C (39.99 °F; 277.59 K)
Related compounds
Related compounds
Ammonia
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Sodium amide or sodamide is an inorganic compound with the formula NaNH2.

Properties

Chemical

Sodium amide reacts with water to release ammonia.

NaNH2 + H2O → NaOH + NH3

Since neutralization releases ammonia, this compound can be used for completely drying wet ammonia gas.

Physical

Sodium amide is a white or gray solid, which reacts violently with water. It is slightly soluble in liq. ammonia.

Availability

Sodium amide is sold by chemical suppliers, though it's almost impossible for the amateur chemist to get hold of it.

Preparation

Sodium amide is commonly prepared by reacting sodium metal with ammonia, in the presence of a catalyst, such as iron(III) nitrate. The reaction is fastest at the boiling point of the ammonia, −33 °C.

Na + NH3 → NaNH2 + ½ H2

A good synthesis procedure can be found here.

Projects

  • Reduce organic compounds
  • Dry ammonia
  • Dehydrohalogenation of halocarbons
  • Cyclization reactions
  • Ethylene oxide synthesis

Handling

Safety

Sodium amide is corrosive and reacts violently with water.

Storage

Sodium amide should be stored in air-tight containers, like Schlenk flasks, under inert gas, like argon and absolutely away from moisture. Ampouling is the best and safest way of storing this compound, especially for long periods of time.

Prolonged contact with air will form a yellow peroxide, which is shock-sensitive and can spontaneously detonate. Sodium amide samples which are yellow or brown in color represent a serious explosion risk.

Disposal

Sodium amide can be safely neutralized by adding it in a large volume of an alcoholic solution, with small amounts of a weak acid, like acetic acid, citric acid, tartaric acid. The acid is required to neutralize the ammonia fumes, but neutralizing this compound will release lots of heat. Therefore, the neutralization solution should be cooled before using and kept cool during the said process. Do this outside.

References

Relevant Sciencemadness threads