Nitrosoguanidine

Nitrosoguanidine[19] is a sensitive primary explosive that produces little heat or flash upon detonation. Although it is a sensitive explosive, detonating from shock, friction, and elevated temperatures, it is not a powerful explosive, very much more gentle in its behavior than mercury fulminate and lead azide.

Properties:
IUPAC NAME: N-methyl-N'-nitro-N-nitroso- guanidine
OTHER NAME: methylnitronitrosoguanidine, MNNG, NTG
MOLECULAR FORMULA: C2H5N5O3
MOLAR MASS: 147.09 g/mol
SHOCK SENSITIVITY: high
FRICTION SENSITIVITY: high

It is a pale yellow crystalline powder which explodes on contact with concentrated sulfuric acid or on being heated in a melting point tube at 165. It explodes from the blow of a carpenter's hammer on a concrete block. Its sensitivity to shock, to friction, and to temperature, and the fact that it decomposes slowly in contact with water at ordinary temperatures, militate against its use as a practical explosive. Because of its sensibility to water it must be kept well sealed to protect from moisture. When properly sealed it can be stored indefinitely.
The reactions of nitrosoguanidine in aqueous solution are similar to those of nitroguanidine except that nitrogen and nitrous acid respectively are formed under conditions which correspond to the formation of nitrous oxide and nitric acid from nitroguanidine. It dearranges principally as follows:

NH2-C(NH)-NH-NO <-> NH2-NO + HNCNH <-> NH2-CN

If it is warmed in aqueous solution, the nitrosoamide breaks down into water and nitrogen, and the cyanamide polymerizes to dicyandiamide. The evaporation of the solution yields crystals of the latter substance. A cold aqueous solution of nitrosoguanidine acidified with hydrochloric acid yields nitrous acid, and may be used for the introduction of a nitroso group into dimethylaniline or some similar substance which is soluble in the acidified aqueous liquid.

At one time a demonstration of how nitrosoguanidine produces no light upon detonation was conducted by a lecturer in a darkened room. Approximately 0.5 g of the explosive is placed on the back of the left hand, a match is lit and extinguished, and the powder is detonated by being touched with the glowing match stick brand. The only after affects to the hand are a rash and peeling of the skin. This surely must have been a crowd pleaser, but, alas, detonating explosives on ones hand is a lost art.