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258 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES

Tetranitrobenzene is a crystalline substance, melting at 129-130°C. In the

presence of moisture it is readily decomposed to form picric acid. When boiled

with water it is fully converted to picric acid. It reacts with ammonia even at room

temperature, forming picramide:

(22)

Holleman gave the following data on the explosive properties of tetranitro-

benzene: sensitiveness to impact - explosion caused by a 2 kg weight falling from

the height of 25 cm; expansion in the lead block = 447 cm

3

.

According to other data, relative sensitiveness to impact is 67 (compared with

picric acid = 100), and relative lead block test expansion amounts to 143 (picric

acid = 100).

Brzozowski [59] gave additional data on the explosive properties of tetranitro-

benzene. He determined the detonation rate of tetranitrobenzene, at a density

of 0.7 g/cm^3 to be 5375 m/sec. At the same density, the detonation rate of trinitro-

benzene is 3990 m/sec, and that of dinitrobenzene is 1795 m/sec.

(The preparation of tetranitrobenzene was first mentioned in the literature by

Nietzki and Dictschy [60] in 1900. The authors described the preparation of the

new compound by the following reactions:

(23)

The product obtained melted at 116°C. However, the results have not been

confirmed by the investigations of other workers. For example, Will [61] boiled
1,2-dinitroso-4,6-dinitrobenzene with nitric acid for 3 hr, but failed to observe

any change in the compound. This is probably due to furoxane structure of
o- dinitroso groups (p. 603).