Magnesium nitride, preparation

Preparation of Magnesium Nitride by Reacting Magnesium with Nitrogen. Assemble an apparatus as shown in Fig. 83 and check its tightness. Fill the apparatus with nitrogen (from a gas meter or cylinder). 

Fig, 83. Apparatus for preparing magnesium nitride by reacting magnesium with nitrogen... 

In general, the nitrides of most of the metals and many of the nonmetals may be prepared by heating the elements together. Owing to the inactivity of nitrogen at ordinary temperatures, it is usually necessary to heat to a very high temperature. Consequently, the formation of nitrides is often observed in electric furnace work. Magnesium nitride is one of the nitrides easiest to prepare. 

Like many other nitrides, magnesium nitride is at once hydrolyzed by contact with water, and even in moist air the odor of ammonia is very noticeable about the preparation. Some of the nitrides are, however, very stable toward water, notably some of the nitrides of phosphorus and titanium. 

Fig. 1.32. Reactions in heated tubes, (a) Apparatus for the preparation and collection of magnesium nitride. Highly purified nitrogen is used, and only the product from the second boat is collected. Sample collection is performed after the tube cools by reversing the nitrogen flow through the apparatus, inserting a long, stiff wire from the right end, and pushing the boat into the Schlenk tube. (h) Preparation of a volatile halide. Very dry gas is used, and its flow rate is carefully adjusted so that the halide neither diffuses back toward the gas source nor is swept past the first bulb. After the reaction is complete, the halide may be resublimed in a gas stream and then sealed off in one or more of the bulbs.

Preparation 14 Magnesium Nitride, Mg3N2 Ammonium Chloride, NH4CI... 

Magnesium nitride is prepared by the same general principle as that employed in preparing aluminum nitride (Preparation 13). If, however, a pile of magnesium were allowed to burn freely in the... 

Magnesium nitride has been used as a sintering aid for silicon nitride powder [178]. It can be prepared by the low pressure CVD of a mixture of elemental metal vapor, ammonia and nitrogen [178]. 

To prepare the pure nitride, magnesium must be burned in a current of pure nitrogen. The latter is now available commercially in compressed form. 

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