The Chemistry of Powder and Explosives - Sciencemadness Dot Org

138 AROMA'llC MTKO COMPOUNDS
1-position Thus, the hydroxyl group of tnnitrophenol is acidic,
and the substance is called picric acid A chlorine atom in the
same position is like the chlonne of an acid chloride (picryl
chloride), an amino group like the ammo of an acid amide (trinitroamhne
is picramide), and a methoxy like the methoxy of an
ester (tnnitroamsol has the reactions of methyl picrate) In general
the picryl group affects the activity of the atom or group to
which it is attached in the same way that the acyl or R—CO—
group does If the picryl group is attached to a carboxyl, the
carboxyl will be expected to lose CO.> readily, as pyruvic acid,
CH3—CO—COOH, does when it is heated with dilute sulfuric
acid, and this indeed happens with the tnnitrobenzoic acid from
which TNB is commonly prepared TNB itself will be expected
to exhibit some of the properties of an aldehyde, of which the
aldehydic hydrogen atom is readily oxidized to an acidic hydroxyl
group, and it is m fact oxidized to picric acid by the action of
pofassium ferncyamde m mildlv alkaline solution 19 We shall see
many examples of the same principle throughout the chemistry of
the explosive aromatic nitro compounds
Tnmtrobenzene is less sensitive to impact than TNT, more
powerful, and more bnsant The detonation of a shell or bomb,
loaded with TNB, m the neighborhood of buildings or other
construction which it is desired to destroy, creates a more damaging
explosive wave than an explosion of TNT, and is more likely
to cause the collapse of walls, etc , which the shell or bomb has
failed to hit Drop tests earned out with a 5-kilogram weight
falling upon several decigrams of each of the vanous explosives
contained m a small cup of iron (0 2 mm thick), covered with a
small iron disc of the same thickness, gave the following figures
for the distances through which the weight must fall to cause
explosion m 50 per cent of the trials.
Trinitrobenzene
Trinitrotoluene
Hexanitrodiphenylamine ammonium salt
Picric acid
Tetryl
Hexanitrodiphenylamine
19 Hepp, Ann , 215, 344 (1882)
CENTIMETERS
150
110
75
65
50
45