Styphnic acid
Encyclopedia
Styphnic acid, or 2,4,6-trinitro-1,3-benzenediol, is a yellow astringent
acid
that forms hexagonal crystal
s. It is used in the manufacture of dye
s, pigment
s, ink
s, medicine
s, and explosives such as lead styphnate
. It is itself a low sensitivity explosive, similar to picric acid
, but explodes upon rapid heating.
with a mixture of nitric
and sulfuric acid
.
This compound is an example of a trinitrophenol
.
Like picric acid
, it is a moderately strong acid, displacing carbon dioxide from solutions of sodium carbonate
for example.
It may be reacted with weakly basic oxides such as those of lead and silver to form the corresponding salts.
The solubility of picric acid
and styphnic acid in water is far less than the non nitrated phenol and less than the corresponding mono and di nitro compounds so they may be purified by fractional crystallisation.
Astringent
An astringent substance is a chemical compound that tends to shrink or constrict body tissues, usually locally after topical medicinal application. The word "astringent" derives from Latin adstringere, meaning "to bind fast"...
acid
Acid
An acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...
that forms hexagonal crystal
Crystal
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...
s. It is used in the manufacture of dye
Dye
A dye is a colored substance that has an affinity to the substrate to which it is being applied. The dye is generally applied in an aqueous solution, and requires a mordant to improve the fastness of the dye on the fiber....
s, pigment
Pigment
A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...
s, ink
Ink
Ink is a liquid or paste that contains pigments and/or dyes and is used to color a surface to produce an image, text, or design. Ink is used for drawing and/or writing with a pen, brush, or quill...
s, medicine
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
s, and explosives such as lead styphnate
Lead styphnate
Lead styphnate , whose name is derived from styphnic acid, is an explosive used as a component in primer and detonator mixtures for less sensitive secondary explosives....
. It is itself a low sensitivity explosive, similar to picric acid
Picric acid
Picric acid is the chemical compound formally called 2,4,6-trinitrophenol . This yellow crystalline solid is one of the most acidic phenols. Like other highly nitrated compounds such as TNT, picric acid is an explosive...
, but explodes upon rapid heating.
Preparation and chemistry
It may be prepared by the nitration of resorcinolResorcinol
Resorcinol is a dihydroxy benzene. It is the 1,3-isomer of benzenediol with the formula C6H42.-Nomenclature:Benzene-1,3-diol is the name recommended by the International Union of Pure and Applied Chemistry in its 1993 Recommendations for the Nomenclature of Organic Chemistry.-Production:It is...
with a mixture of nitric
Nitric acid
Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...
and sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
.
This compound is an example of a trinitrophenol
Phenols
In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of a hydroxyl group bonded directly to an aromatic hydrocarbon group...
.
Like picric acid
Picric acid
Picric acid is the chemical compound formally called 2,4,6-trinitrophenol . This yellow crystalline solid is one of the most acidic phenols. Like other highly nitrated compounds such as TNT, picric acid is an explosive...
, it is a moderately strong acid, displacing carbon dioxide from solutions of sodium carbonate
Sodium carbonate
Sodium carbonate , Na2CO3 is a sodium salt of carbonic acid. It most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. Sodium carbonate is domestically well-known for its everyday use as a water softener. It can be extracted from the...
for example.
It may be reacted with weakly basic oxides such as those of lead and silver to form the corresponding salts.
The solubility of picric acid
Picric acid
Picric acid is the chemical compound formally called 2,4,6-trinitrophenol . This yellow crystalline solid is one of the most acidic phenols. Like other highly nitrated compounds such as TNT, picric acid is an explosive...
and styphnic acid in water is far less than the non nitrated phenol and less than the corresponding mono and di nitro compounds so they may be purified by fractional crystallisation.