Picric acid
General
Systematic name	2,4,6-trinitrophenol
Other names	Carbazotic Acid phenol trinitrate picronitric acid trinitrophenol 2-hydroxy-1,3,5-trinitrobenzene
Molecular formula	(NO2)3C6H2OH
SMILES	Oc1c(N(=O)=O)cc (N(=O)=O)cc1N(=O)=O
Molar mass	229.1056 g/mol
Appearance	Colorless-yellow solid.
CAS number	[88-89-1] [1]
Properties
Density and phase	1.763 g/cm³, solid.
Solubility in water	1.40 g/100 ml (?°C)
Melting point	122.5°C (395.65 K)
Boiling point	Explodes > 300°C (573.15 K)
Acidity (pKa)	0.38
Structure
Molecular shape	Planar.
Crystal structure	?
Dipole moment	? D
Hazards
MSDS	External MSDS
Main hazards	Explosive, flammable, irritant, toxic.
NFPA 704	Image File history File links Picric_acid. ... IUPAC nomenclature is a system of naming chemical compounds and of describing the science of chemistry in general. ... A chemical formula (also called molecular formula) is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... The simplified molecular input line entry specification or SMILES is a specification for unambiguously describing the structure of chemical molecules using short ASCII strings. ... Molar mass is the mass of one mole of a chemical element or chemical compound. ... CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. ... Density (symbol: ρ - Greek: rho) is a measure of mass per volume. ... In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i. ... It has been suggested that Solid solubility be merged into this article or section. ... This article describes water from a scientific and technical perspective. ... The melting point of a solid is the temperature at which it changes state from solid to liquid. ... The boiling point of a substance is the temperature at which it can change its state from a liquid to a gas throughout the bulk of the liquid at a given pressure. ... In chemistry and biochemistry, the acid dissociation constant, the acidity constant, or the acid-ionization constant (Ka) is a specific type of equilibrium constant that indicates the extent of dissociation of hydrogen ions from an acid. ... four sp³ orbitals three sp² orbitals In chemistry, hybridisation or hybridization (see spelling differences) is the mixing of atomic orbitals belonging to a same electron shell to form new orbitals suitable for the qualitative description of atomic bonding properties. ... Enargite crystals In mineralogy and crystallography, a crystal structure is a unique arrangement of atoms in a crystal. ... // The Earths magnetic field, which is approximately a dipole. ... The debye (symbol: D) is a non-SI and non-CGS unit of electrical dipole moment. ... A material safety data sheet or MSDS is a form containing data regarding the properties of a particular substance. ... The examples and perspective in this article or section may not represent a worldwide view. ... NFPA 704 is a standard maintained by the U.S. National Fire Protection Association. ... Image File history File links NFPA_704. ... 4 3 4 OX
Flash point	150°C
R/S statement	R: R1, R10, R36, R37, R38. S: S28, S35, S37, S45.
RTECS number	TJ7875000
Supplementary data page
Structure and properties	n, εr, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Related Phenols	?
Related compounds	?
Except where noted otherwise, data are given for materials in their standard state (at 25°C, 100 kPa) Infobox disclaimer and references

Picric acid is the common term for the chemical compound 2,4,6-trinitrophenol, also known as TNP; the material is a yellow crystalline solid. Like other highly nitrated compounds (e.g. trinitrotoluene), picric acid is an explosive. The flash point of a flammable liquid is the lowest temperature at which it can form an ignitable mixture with air. ... Risk and Safety Statements, also known as R/S statements, R/S numbers, R/S phrases, and R/S sentences, is a system of hazard codes and phrases for labeling dangerous chemicals and compounds. ... R-phrases are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations. ... S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. ... RTECS, also known as Registry of Toxic Effects of Chemical Substances, is a database of toxicity information compiled from the open scientific literature that is available for charge. ... The refractive index (or index of refraction) of a material is the factor by which the phase velocity of electromagnetic radiation is slowed in that material, relative to its velocity in a vacuum. ... The dielectric constant εr (represented as or K in some cases) is defined as the ratio: where εs is the static permittivity of the material in question, and ε0 is the vacuum permittivity. ... Ultraviolet-Visible Spectroscopy or Ultraviolet-Visible Spectrophotometry (UV/ VIS) involves the spectroscopy of photons (spectrophotometry). ... IR spectrum of a thin film of liquid ethanol. ... Nuclear Magnetic Resonance Spectroscopy most commonly known as NMR Spectroscopy is the name given to the technique which exploits the magnetic properties of nuclei. ... Basic schematic of a mass spectrometer Mass spectrometry (also known as mass spectroscopy (deprecated)[1] or in common speech mass-spec) is an analytical technique used to measure the mass-to-charge ratio of ions. ... Phenol, also known under an older name of carbolic acid, is a colorless crystalline solid with a typical sweet tarry odor. ... In chemistry, the standard state of a material is its state at 1 bar (100 kilopascals) and 25 degrees Celsius (298. ... A chemical compound is a chemical substance consisting of two or more different chemically bonded chemical elements, with a fixed ratio determining the composition. ... Crystal (disambiguation) Insulin crystals A crystal is a solid in which the constituent atoms, molecules, or ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions. ... In jewelry, a solid gold piece is the alternative to gold-filled or gold-plated jewelry. ... An electrostatic potential map of the nitrate ion. ... Trinitrotoluene (TNT) is an explosive. ... This article is concerned solely with chemical explosives. ...

Modern safety precautions recommend storing picric acid wet. When picric acid is dry, it is relatively sensitive to shock and friction, so laboratories that use it store it in bottles under a layer of water, rendering it safe. Glass or plastic bottles are required, as picric acid can form metal picrate salts that are even more sensitive and hazardous than the acid. Shock is a serious medical condition where the tissue perfusion is insufficient to meet the required supply of oxygen and nutrients. ... It has been suggested that Coefficient of friction be merged into this article or section. ... This article describes water from a scientific and technical perspective. ... A magnified crystal of a salt (halite/sodium chloride) In chemistry, a salt is any ionic compound composed of positively charged cations and negatively charged anions so that the product is neutral and without a net charge. ...

Modern safety precautions for plain picric acid are moderately overstated, as it was used successfully as an explosive filler for most artillery shells and bombs in the First World War. Those applications necessarily subject it to shock and friction during firing of the shells.

Properties

• Velocity of detonation: 7,350 m/s at density 1.70
• Autoignition temperature: Explodes over 300 °C

Picric acid can be made from phenol, benzene, or even acetylsalicylic acid (aspirin). A weapons cache is detonated at the East River Range on Bagram Airfield, Afghanistan Detonation is a process of supersonic combustion that involves a shock wave and a reaction zone behind it. ... The autoignition temperature of a substance is the lowest temperature at which a chemical will spontaneously combust in a normal atmosphere, without an external source of ignition, such as a flame or spark. ... Phenol, also known under an older name of carbolic acid, is a colorless crystalline solid with a typical sweet tarry odor. ... Benzene, also known as benzol, is an organic chemical compound with the formula C6H6. ... Aspirin or acetylsalicylic acid (acetosal) is a drug in the family of salicylates, often used as an analgesic (against minor pains and aches), antipyretic (against fever), and anti-inflammatory. ...

History

Picric acid was first mentioned in the alchemical writings of Glauber in 1742. Initially, it was made by nitrating substances such as animal horn, silk, indigo, and natural resin. Its synthesis from phenol, and the correct determination of its formula, were successfully accomplished in 1841. Not until 1830 did chemists think to use picric acid as an explosive. Before then, chemists assumed that only the salts of picric acid were explosive, not the acid itself. In 1873 Hermann Sprengel proved it could be detonated and by 1894 the Russians had worked out a method of manufacture for artillery shells. Soon after, every military power used picric acid as their primary high explosive material. The 20th century saw the decline of picric acid, the replacement being TNT. Shells filled with picric acid become highly unstable as the compound reacts with the metal bomb shell, forming extremely sensitive metal picrates, making them unusable. Today picric acid is more suited to detonators or booster charges. It is also used in the analytical chemistry of metals, ores, and minerals. The Alchemist. ... Glauber is a discovery system type of artificial intelligence that is used to discover new chemical theories based on empirical evidence and the systematic measurement of related data. ... // Events January 24 - Charles VII Albert becomes Holy Roman Emperor. ... Nitration is a general chemical process for the introduction of a nitro group in a chemical compound by means of a chemical reaction. ... Silk weaver Silk is a natural protein fibre that can be woven into textiles. ... Indigo is the color of light between 440 to 420 nanometres in wavelength, placing it between blue and violet. ... Resin of a pine Insect trapped in resin. ... Phenol, also known under an older name of carbolic acid, is a colorless crystalline solid with a typical sweet tarry odor. ... 1841 is a common year starting on Friday (link will take you to calendar). ... Liberty Leading the People by Eugène Delacroix commemorates the July Revolution 1830 was a common year starting on Friday (see link for calendar). ... This article is concerned solely with chemical explosives. ... For other meanings of the word salt see table salt or salt (disambiguation). ... This article is concerned solely with chemical explosives. ... 1873 (MDCCCLXXIII) was a common year starting on Wednesday (see link for calendar). ... Hermann Sprengel (1834-1906) was a German chemist. ... 1894 (MDCCCXCIV) was a common year starting on Monday (see link for calendar). ... This article is concerned solely with chemical explosives. ... Trinitrotoluene (TNT) is an explosive. ...

Picric acid was one of the main components in the Halifax explosion. It has been suggested that Imo (ship) be merged into this article or section. ...

In 1885, based on research of Hermann Sprengel, French chemist Eugene Turpin patented the use of pressed and cast picric acid in blasting charges and artillery shells. In 1887 the French government adopted it under the name melinite, with addition of gun cotton. Since 1888, Britain started manufacturing a very similar mixture in Lydd, Kent, under the name lyddite. Japan followed with an improved formula known as schimose. In 1889, a similar material, a mixture of ammonium cresylate with trinitrocresol, or an ammonium salt of trinitrocresol, started to be manufactured under the name ecrasite. François Eugene Turpin was a French chemist involved in research of explosive materials. ... Rock blasting is the controlled use of explosives to excavate rock. ... A shell is a projectile, which, as opposed to a bullet, is not solid but contains an explosive or other filling. ... Nitrocellulose (Cellulose nitrate, guncotton) is a highly flammable compound formed by nitrating cellulose (e. ... Location within the British Isles Arms of Lydd Town Council Lydd is a town in Kent, England, lying on the Romney Marsh. ... Ecrasite is an explosive material which is unaffected by moisture, shock or fire. ...

Uses

By far the largest use has been in munitions and explosives; it was known in World War I as Lyddite (from Lydd, Kent, where the British undertook work to develop it as a shell filling) or Melinite. Boxes of ammunition clog a warehouse in Baghdad Ammunition is a generic military term meaning (the assembly of) a projectile and its propellant. ... Combatants Allied Powers: France Italy Russia Serbia United Kingdom United States Central Powers: Austria-Hungary Bulgaria Germany Ottoman Empire Commanders Ferdinand Foch Georges Clemenceau Victor Emmanuel III Luigi Cadorna Nicholas II Aleksei Brusilov Herbert Henry Asquith Douglas Haig John Jellicoe Woodrow Wilson John Pershing Wilhelm II Paul von Hindenburg Reinhard... Location within the British Isles Arms of Lydd Town Council Lydd is a town in Kent, England, lying on the Romney Marsh. ...

The principal laboratory use of picric acid is in microscopy, where it is used as a reagent for staining samples, e.g. Gram staining. It has been suggested that this article or section be merged into microscope. ... Gram-positive anthrax bacteria (purple rods) in cerebrospinal fluid sample. ...

Bouin's picro-formol is a preservative solution used for biological specimens.

Much less commonly, wet picric acid has been used as a skin dye or temporary branding agent. It is not acidic enough to cause chemical burns, and reacts with proteins in the skin to give a dark brown color that may last as long as a month.

Other

Picric acid is well known as another easy 'homemade explosive,' since its synthesis requires chemicals that can be bought at the store. Many people have injured or killed themselves during the synthesis of picric acid. During its synthesis the highly toxic nitrogen dioxide gas can result. [1] R-phrases , S-phrases , , , , , Supplementary data page Structure and properties n, εr, etc. ...

See also

• Explosives
• Nitroglycerin
• Trinitrotoluene

This article is concerned solely with chemical explosives. ... Nitroglycerin, also known as nitroglycerine, trinitroglycerin, and glyceryl trinitrate, is a chemical compound. ... Trinitrotoluene (TNT) is an explosive. ...

External links

• Safety Information

• Link page to external chemical sources.

References

• Cooper, Paul W., Explosives Engineering, New York: Wiley-VCH, 1996. ISBN 0-471-18636-8