PICRIC ACID

Picric acid is a versatile aromatic nitro compound widely used in analytical chemistry, histology, microscopy, metallography, and specialized laboratory applications where its strong acidity and distinctive chemical behavior provide reliable performance in controlled procedures.
Picric acid's highly substituted phenolic structure makes it valuable in qualitative analysis, staining and fixation formulations, metal surface examination, and selected organic synthesis processes requiring a strongly electron-deficient aromatic intermediate.
With carefully controlled moisture content, storage conditions, and handling practices, Picric acid can serve as an effective specialty reagent for research, industrial analysis, and technical laboratory operations

CAS Number: 88-89-1
EC Number: 201-865-9ChEBI: CHEBI:46149
Molecular Formula: C6H3N3O7
Molecular Weight: 229.11 g/mol

Synonyms: 1-Hydroxy-2,4,6-trinitrobenzene, 2,4,6-Trinitrofenol, 2,4,6-Trinitrofenolo, 2,4,6-Trinitrophenol, 2,4,6-Trinitrophénol, 2,4,6-Trinitrophenol, 2-Hydroxy-1,3,5-trinitrobenzene, 201-865-9, 423400, 88-89-1, acide picrique, Acido picrico, Acidum picrinicum, Phenol, 2,4,6-trinitro-, Picric acid, Pikrinsaeure, WNR BQ CNW ENW, 1-methyl-3,4-dihydro-2H-β-carboline, 2,4,6-Trinitrofenolo, 200-835-2, 6954 [PubChem CID], acide picrique, Acidum picrinicum, ADRB2_HUMAN, Carbazotic acid, DTXSID4025909 [Comptox], Hager's reagent, Kyselina pikrova, Kyselina pikrova, Mannose-6-phosphate isomerase, Melinite, MPI_HUMAN, Nitroxanthic acid, Pertite, Phenol trinitrate, Phenoltrinitrate, Picragol, Picral, Picricum acidum, Picronitric acid, Picrotol, Pikrinezuur, Pikrinsaeure, Pikrynowy kwas, Pikrynowy kwas, Protein RecA, RECA_MYCTU, Reflorit, TJ7875000 [RTECS], TNF, TNP, TRINITROPHENOL, β-2 adrenergic receptor, 苦味酸, Picric acid, 2,4,6-Trinitrophenol, Trinitrophenol, 88-89-1, Carbazotic acid, Picronitric acid, Melinite, Acide picrique, Nitroxanthic acid, Phenol trinitrate, Picral, Pikrinezuur, Pikrinsaeure, Acido picrico, Pikrynowy kwas, Phenol, 2,4,6-trinitro-, Phenoltrinitrate, 2-Hydroxy-1,3,5-trinitrobenzene, Picricum acidum, Kyselina pikrova, Acidum picrinicum, 1,3,5-Trinitrophenol, 2,4,6-Trinitrofenol, 2,4,6-Trinitrofenolo, 2,4,6-Trinitrophenyl, C.I. 10305, NSC 36947, CI 10305, NSC-36947, A49OS0F91S, DTXSID4025909, CHEBI:46149, Acidum Picricum, 1-hydroxy-2,4,6-trinitrobenzene, San Su, RefChem:6142, DTXCID905909, 201-865-9, Picric acid, dry, Picric acid, wet, 2,6-Trinitrofenol, Pertite, Picric acid (dry), Picric acid (wet), 1,5-Trinitrophenol, 2,6-Trinitrofenolo, 2,6-Trinitrophenol, Phenol,4,6-trinitro-, WLN: WNR BQ CNW ENW, 2-Hydroxy-1,5-trinitrobenzene, Pikrinezuur [Dutch], Pikrinsaeure [German], Acide picrique [French], Acido picrico [Italian], Pikrynowy kwas [Polish], Kyselina pikrova [Czech], CCRIS 3106, Trinitrophenol [NF], 2,4,6-Trinitrofenol [Dutch], HSDB 2040, 2,4,6-Trinitrofenolo [Italian], EINECS 201-865-9, NA1344, UN0154, UN1344, UNII-A49OS0F91S, Reflorit, AI3-15403, C6H3N3O7, Hager's reagent, Picric acid, p.a., Lyddite (Salt/Mix), Ecrasite (Salt/Mix), Schimose (Salt/Mix), Picric acid [MI], Picric acid [HSDB], SCHEMBL8744, NA 1344 (Salt/Mix), UN 1344 (Salt/Mix), Picric acid [WHO-DD], PICRICUM ACIDUM [HPUS], TRINITROPHENOL [MART.], CHEMBL108541, SCHEMBL4076110, Picric acid, dry or wetted with < 30% water, by mass, SCHEMBL14419782, BDBM34612, cid_3241713, Trinitrophenol, dry or wetted with < 30% water, by mass, NSC36947, NSC56147, NSC-56147, STL199171, AKOS008966816, DB03651, UN 0154, Picric acid, wet, with not <10% water, DB-057108, Picric acid, moistened with water, >=98%, NS00010581, Picric acid, SAJ special grade, >=99.5%, 2-methylbenzo[g][1,3]benzoxazole;Picric acid, Picric acid solution (naturally short expiry), Picric acid solution (1.3% in H2O, saturated), Picric acid, ACS grade, wetted with > 30% water, Q189298, SR-01000944524, 1-methyl-3,4-dihydro-2H-beta-carboline;Picric acid, 2,4,6-Trinitrophenol 10 microg/mL in Acetonitrile, SR-01000944524-1, 2,4,6-Trinitrophenol 100 microg/mL in Acetonitrile, Trinitrophenol, wetted with not <30% water, by mass, 2-methylbenzo[g][1,3]benzoxazole;2,4,6-trinitrophenol, Picric acid solution, 1.3% wt/wt in water (saturated), Picric acid, wet, with not <10% water [NA1344] [Flammable solid], Trinitrophenol or Picric acid, dry or wetted with <30% water, by mass, Trinitrophenol, wetted with not <30% water, by mass [UN1344] [Flammable solid], InChI=1/C6H3N3O7/c10-6-4(8(13)14)1-3(7(11)12)2-5(6)9(15)16/h1-2,10, Picric acid wetted with water (sold on a dry weight bases, 100 g unit=100 g Picric acid + approx. 140 g water), Trinitrophenol or Picric acid, dry or wetted with <30% water, by mass [UN0154] [Explosive 1.1D]

Picric acid is an organic compound with the formula (O2N)3C6H2OH.
Picric acid's IUPAC name is 2,4,6-trinitrophenol (TNP).

The name "picric" comes from Greek: πικρός (pikros), meaning "bitter", due to its bitter taste.
Picric acid is one of the most acidic phenols. Like other strongly nitrated organic compounds, Picric acid is an explosive, which is its primary use.
Picric acid has also been used as medicine (antiseptic, burn treatments) and as a dye.

Picric acid is flammable, highly explosive, nitrated organic compound.
Primarily used in munitions and explosives, Picric acid's other applications include use in the Jaffe reaction and the preparation of crystalline salts of organic bases.

Picric acid is a polynitrated aromatic acid.
Picric acid is strongly acidic in nature.

Since it readily dissolves in water, Picric acid can easily pollute the environment on exposure.
Sensitive detection of PA by tris-imidazolium salt, fluorescent [3+2] self-assembled nanoscopic organic cage and rhodamine based sensors have been reported.
Picric acid is widely used for the determination of various organic compounds by spectrophotometric and extractive spectrophotometric methods.

Picric acid is common in laboratories.
Picric acid is normally sold containing 10 to 15% water in a plastic-capped glass container and, in this state, is relatively safe to handle.

Dry Picric acid, however, can explode when exposed to friction, shock, or sudden heating.
Moreover, Picric acid can form salts on contact with metals, and heavy metal picrates are highly sensitive to detonation.

Picric acid is a highly versatile compound with significant applications in various fields, including pharmaceuticals, explosives, and dye manufacturing.
Picric acid is recognized for Picric acid's strong acidic properties and ability to form stable salts with metals, making it a valuable reagent in organic synthesis.

In the pharmaceutical industry, Picric acid serves as an important intermediate in the production of various medicinal compounds, while its explosive properties have historically made it a key component in military munitions.
Additionally, Picric acid is utilized in the dye industry for the synthesis of azo dyes, which are widely used in textiles and food products.

Researchers and industry professionals appreciate Picric acid for its unique ability to act as a nitrating agent, facilitating the introduction of nitro groups into organic molecules.
This characteristic enhances Picric acid's utility in developing new compounds with desired properties.

Furthermore, Picric acid's stability under certain conditions makes it a reliable choice for various applications.
With its broad range of uses and significant impact across multiple sectors, Picric acid remains an essential compound for innovation and development in chemical research and industry.

Picric acid is a yellow crystalline solid and one of the most acidic phenols.
As a highly nitrated compound, Picric acid is highly explosive (like TNT).

Apart from it's use as an explosive, Picric acid also has some uses in organic chemistry for the preparation of crystalline salts of organic bases.
Picric acid is also used in clinical chemistry for the Jaffe reaction (a colorimetric method to determine creatinine levels in blood and urine).

Picric acid is a chemical compound that is commonly used in military explosives and has various other applications such as dyeing textiles, staining materials, and as a component of rocket fuel.
Picric acid is also used in the production of matches, electric batteries, and as a sensitizer in photographic emulsions.

Picric acid is an aromatic nitro compound with the molecular formula C6H3N3O7, also known as 2,4,6-trinitrophenol.
Picric acid is typically encountered as a yellow crystalline solid and contains three nitro groups attached to a phenolic ring, giving it strongly acidic character compared with ordinary phenols.
Picric acid has been used in chemical analysis, dye chemistry, laboratory reagents, metal characterization, and as an intermediate in specialized chemical synthesis.

Applications of Picric Acid:
Picric acid has been used in the preparation of Bouin′s fixative and Picric acid/sodium azide/multi-walled carbon nanotubes.
Picric acid was used in the quantitative determination of bisoprolol.

Picric acid is used as an explosive, dye, fungicide, copper etching agent, and chemical intermediate for metal picrates.
Picric acid is used in the manufacturing of leather products, batteries, colored glass, textile mordants, rocket fuel, and photographic emulsions.

Picric acid is used in synthesis of dyes.
Picric acid was used as solvent for extraction of insulin from human tissue.

Picric acid is used in laboratories as a chemical reagent.
Picric acid has been used as an explosive and in the production of batteries.

Picric acid has also been used in the leather and textile industry and in the production of coloured glass and dyes.
In the 20th century Picric acid was used as an antiseptic in medical ointments to treat wounds including burns.

Picric acid is used as a laboratory reagent in chemical analysis and qualitative testing.
Picric acid is applied in histology and microscopy as a component of staining and fixation solutions.

Picric acid is used in certain metallographic etching formulations for examining metal and alloy microstructures.
Picric acid serves as an intermediate in the production of selected dyes, pigments, and specialty organic compounds.

Picric acid has also been used in analytical methods for detecting or determining various organic and inorganic substances.
Historically, Picric acid was used in energetic compositions, although modern applications are more commonly focused on laboratory, analytical, and specialty chemical uses.

Uses of Picric Acid:
By far the greatest use of Picric acid has been in ammunition and explosives.

Derivatives:
Ammonium picrate (Explosive D, also known as Dunnite), is the ammonium salt of Picric acid.
Picric acid is notably less sensitive to impact than either Picric acid or TNT (16–17 in (41–43 cm) initiation drop height using the Picatinny Arsenal apparatus, vs. 12–14 in (30–36 cm) for TNT and 13 in (33 cm) for PA), which allowed its use in armor piercing ammunition.
Ammonium picrate was used by the United States army beginning in 1901 and the navy in 1907.

Picramide, formed by aminating Picric acid (typically beginning with Dunnite), can be further aminated to produce the very stable explosive TATB.
Picric acid has found some use in organic chemistry for the preparation of crystalline salts of organic bases (picrates) for the purpose of identification and characterization.

Optical metallography:
In metallurgy, a 4% Picric acid in ethanol etch, termed "picral", has been commonly used in optical metallography to reveal prior austenite grain boundaries in ferritic steels.
The hazards associated with Picric acid have meant Picric acid has largely been replaced with other chemical etchants.
However, Picric acid is still used to etch magnesium alloys, such as AZ31.

Histology:
Bouin solution is a common picric-acid–containing fixative solution used for histology specimens.
Picric acid improves the staining of acid dyes, but it can also result in hydrolysis of any DNA in the sample.

Picric acid is used in the preparation of Picrosirius red, a histological stain for collagen.

Blood tests:
Clinical chemistry laboratory testing utilizes Picric acid for the Jaffe reaction to test for creatinine.
Picric acid forms a colored complex that can be measured using spectroscopy.

Picric acid forms red isopurpurate with hydrogen cyanide (HCN).
By photometric measurement of the resulting dye, Picric acid can be used to quantify hydrogen cyanide.

During the early 20th century, Picric acid was used to measure blood glucose levels.
When glucose, Picric acid and sodium carbonate are combined and heated, a characteristic red color forms.

With a calibrating glucose solution, the red color can be used to measure the glucose levels added.
This is known as the Lewis and Benedict method of measuring glucose.

Skin dye:
Much less commonly, wet Picric acid has been used as a skin dye, or temporary branding agent.
Picric acid reacts with proteins in the skin to give a dark brown color that may last as long as a month.

Antiseptic:
During the early 20th century, Picric acid was stocked in pharmacies as an antiseptic and as a treatment for burns, malaria, herpes, and smallpox.
Picric-acid–soaked gauze was commonly stocked in first aid kits from that period as a burn treatment.
Picric acid was notably used for the treatment of burns suffered by victims of the Hindenburg disaster in 1937.

Picric acid was used as a treatment for trench foot suffered by soldiers on the Western Front during World War I.

Picric acid has been used for many years by fly tyers to dye mole skins and feathers a dark olive green for use as fishing lures.
Picric acid's popularity has been tempered by its toxic nature.

Synthesis of Picric Acid:
The aromatic ring of phenol is activated towards electrophilic substitution reactions, and attempted nitration of phenol, even with dilute nitric acid, results in the formation of high molecular weight tars.
In order to minimize these side reactions, anhydrous phenol is sulfonated with fuming sulfuric acid, and the resulting sulfonic acid is then nitrated with concentrated nitric acid.

During this reaction, nitro groups are introduced, and the sulfonic acid group is displaced.
The reaction is highly exothermic, and careful temperature control is required.

Synthesis routes that nitrate aspirin or salicylic acid can also be used to mitigate tar formation.
Carbon dioxide is lost from the former via decarboxylation, while both acetic acid and carbon dioxide are lost from the latter.
Another method of Picric acid synthesis is direct nitration of 2,4-dinitrophenol with nitric acid.

History of Picric Acid:
Picric acid was probably first mentioned in the 17th-century alchemical writings of Johann Rudolf Glauber.
Initially, Picric acid was made by nitrating substances such as animal horn, silk, indigo, and natural resin, the synthesis from indigo first being performed by Peter Woulfe in 1771.

The German chemist Justus von Liebig had named Picric acid Kohlenstickstoffsäure (rendered in French as acide carboazotique).
Picric acid was given that name by the French chemist Jean-Baptiste Dumas in 1841.

Picric acid's synthesis from phenol, and the correct determination of its formula, were accomplished during 1841.
In 1799, French chemist Jean-Joseph Welter (1763–1852) produced Picric acid by treating silk with nitric acid; he found that potassium picrate could explode.

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.

A theory to explain why picrate salts detonated whereas Picric acid itself didn't, was proposed by the French chemists Antoine Fourcroy and Louis Vauquelin in 1806 and reiterated by the French chemist Michel Chevreul in 1809.
Picric acid evidently contained enough oxygen within itself—i.e. it was "super-oxygenated" (suroxigéné)—to combust completely even in the absence of air (because even in the absence of air, heat could transform it completely into gases, leaving no carbon).

However, when Picric acid was burned, the heat that was generated caused some of the acid to evaporate, dissipating so much heat that only burning, not detonation, occurred.
In contrast, picrate salts were solids that did not sublimate, thus did not dissipate heat; hence, they did detonate.

In 1871 Hermann Sprengel proved Picric acid could be detonated at the gunpowder works of John Hall & Sons in Faversham in Kent, England.
Sprengel filed patents in Britain for "safety explosives" (i.e., stable explosives) on April 6, 1871 (no. 921) and on October 5, 1871 (no. 2642); in the latter patent, Sprengel proposed using Picric acid dissolved in nitric acid as an explosive.

Afterwards most military powers used Picric acid as their main high explosive material.
A full synthesis was later found by Leonid Valerieovich Kozakov.

Picric acid was the first strongly explosive nitrated organic compound widely considered suitable to withstand the shock of firing in conventional artillery.
Nitroglycerine and nitrocellulose (guncotton) were available earlier, but shock sensitivity sometimes caused detonation in an artillery barrel at the time of firing.

In 1885, based on research of Hermann Sprengel, French chemist Eugène Turpin patented the use of pressed and cast Picric acid in blasting charges and artillery shells.

In 1887 the French government adopted a mixture of Picric acid and guncotton with the name Melinite.
In 1888, Britain started manufacturing a very similar mixture in Lydd, Kent, with the name Lyddite.
Japan followed with an alternative stabilization approach known as Shimose powder which, instead of attempting to stabilize the material itself, removed Picric acid's contact with metal by coating the inside of the shells with layer(s) of resin and wax.

By 1894 Russia was manufacturing artillery shells filled with Picric acid.
However, shells filled with Picric acid become unstable if the compound reacts with the metal shell or fuze casings to form metal picrates which are more sensitive than the parent phenol.
The sensitivity of Picric acid was demonstrated by the Halifax Explosion.

Picric acid was used in the Battle of Omdurman, the Second Boer War, the Russo-Japanese War, and World War I.

Germany began filling artillery shells with trinitrotoluene (TNT) in 1902.
Toluene was less readily available than phenol, and TNT is slightly less powerful than Picric acid, but the improved safety of munitions manufacturing and storage caused the replacement of Picric acid by TNT for most military purposes between the World Wars.

Efforts to control the availability of phenol, the precursor to Picric acid, emphasize its importance in World War I.
Germans are reported to have bought US supplies of phenol and converted it to acetylsalicylic acid (aspirin) to keep it from the Allies.

At the time, phenol was obtained from coal as a co-product of coke ovens and the manufacture of gas for gas lighting.
Laclede Gas reports being asked to expand production of phenol (and toluene) to assist the war effort.

Both Monsanto and Dow Chemical began manufacturing synthetic phenol in 1915, with Dow being the main producer.
Dow describes Picric acid as "the main battlefield explosive used by the French.
Large amounts [of phenol] also went to Japan, where it was made into Picric acid sold to the Russians."

Stability and Reactivity of Picric Acid:

Chemical stability:
Picric acid is more stable when maintained in its specified wetted condition; dry material is highly sensitive to heat, shock, and friction.

Conditions to avoid:
Avoid drying, excessive heat, flames, sparks, friction, impact, and electrostatic discharge.

Incompatible materials:
Avoid strong oxidizing or reducing agents, strong bases, ammonia, and contact with metals such as copper, lead, zinc, iron, and mercury because sensitive metal picrates may form.

Handling and Storage of Picric Acid:

Safe handling:
Handle only with appropriate training, avoid dust formation, and keep away from ignition sources, friction, impact, and incompatible materials.

Storage conditions:
Keep the container tightly closed in a cool, well-ventilated designated area and maintain the material in its specified wetted condition; do not allow it to dry out.

First Aid Measures of Picric Acid:

Inhalation:
Move the affected person to fresh air and obtain medical attention.

Skin contact:
Remove contaminated clothing and wash the affected skin thoroughly with water and soap.

Eye contact:
Rinse cautiously with plenty of water for several minutes and obtain medical attention if irritation persists.

Ingestion:
Rinse the mouth, do not induce vomiting, and obtain immediate medical attention.

Firefighting Measures of Picric Acid:

Fire response:
Because heated or dried Picric acid may explode, evacuate the area and allow trained emergency personnel to manage the incident from a protected location.

Hazardous decomposition products:
Combustion or decomposition may generate carbon oxides, nitrogen oxides, and irritating fumes.

Accidental Release Measures of Picric Acid:

Personal precautions:
Eliminate ignition sources, evacuate unnecessary personnel, and avoid touching, walking through, or disturbing spilled material.

Cleanup methods:
Do not attempt routine cleanup of dry, crystallized, or potentially unstable Picric acid; isolate the area and obtain assistance from qualified hazardous-materials or explosives personnel.

Exposure Controls/Personal Protection of Picric Acid:

Engineering controls:
Use adequate ventilation and appropriate engineering controls to minimize dust and airborne exposure.

Eye protection:
Wear suitable chemical safety goggles or equivalent eye protection.

Hand protection:
Wear suitable chemical-resistant protective gloves.

Body protection:
Use appropriate protective clothing to prevent skin contact.

Respiratory protection:
Use suitable respiratory protection when airborne exposure cannot be adequately controlled by ventilation.

Identifiers of Picric Acid:
Article No.: 05281
Grade: AR
Purity: 99.8%
CAS No.: 88-89-1
Molecular Formula: C6H3N3O7
Molecular Weight: 229.11
H.S. Code: 2908.9990

CAS Number: 88-89-1
3D Model (JSmol): Interactive image
ChEBI: CHEBI:46149
ChEMBL: ChEMBL108541
ChemSpider: 6688
DrugBank: DB03651
ECHA InfoCard: 100.001.696
PubChem CID: 6954
RTECS Number: TJ7875000
UNII: A49OS0F91S
UN Number: UN1344
CompTox Dashboard (EPA): DTXSID4025909
InChI: InChI=1S/C6H3N3O7/c10-6-4(8(13)14)1-3(7(11)12)2-5(6)9(15)16/h1-2,10H
Key: OXNIZHLAWKMVMX-UHFFFAOYSA-N
InChI: InChI=1/C6H3N3O7/c10-6-4(8(13)14)1-3(7(11)12)2-5(6)9(15)16/h1-2,10H
Key: OXNIZHLAWKMVMX-UHFFFAOYAM
SMILES: O=[N+]([O-])c1cc(cc([N+]([O-])=O)c1O)[N+]([O-])=O

Linear Formula: (O2N)3C6H2OH
CAS Number: 88-89-1
Molecular Weight: 229.10
UNSPSC Code: 12352100
PubChem Substance ID: 57647805
MDL Number: MFCD00007102
Colour Index Number: 10305
Beilstein/REAXYS Number: 423400
Assay: ≥98%
Concentration: ≥50-<70%
Form: powder or crystals (with a top layer of Liquid)

Properties of Picric Acid:
Chemical Formula: C6H3N3O7
Molar Mass: 229.104 g·mol−1
Appearance: Colorless to yellow solid
Density: 1.763 g/cm3, solid
Melting Point: 122.5 °C (252.5 °F; 395.6 K)
Boiling Point: Sublimes above MP
Solubility in Water: 12.7 g/L
Solubility in Sulfuric Acid: 10.18 g/100g sln. (18 °C (64 °F; 291 K))
Solubility in Sulfuric Acid: 16.23 g/100g sln. (50 °C (122 °F; 323 K))
Solubility in Sulfuric Acid: 25.86 g/100g sln. (80 °C (176 °F; 353 K))
Solubility in Sulfuric Acid: (in 100% H2SO4)
Solubility in Ethanol: 7.452 g/100g
Solubility in Diethyl Ether: 1.08 g/100g (13 °C (55 °F; 286 K))
Solubility in Benzene: 5.9 g/100g (15 °C (59 °F; 288 K))
Solubility in Toluene: 12.0 g/100ml (20 °C (68 °F; 293 K))
Solubility in Amyl Alcohol: 1.755 g/100ml (20 °C (68 °F; 293 K))
Log P: 1.33
Vapor Pressure: 2 mmHg (0.27 kPa) (195 °C (383 °F; 468 K))
Vapor Pressure: 50 mmHg (6.7 kPa) (255 °C (491 °F; 528 K))
Acidity (pKa): 0.38
Magnetic Susceptibility (χ): −84.34×10−6 cm3/mol

Vapor Density: 7.9 (vs air)
Quality Segment: 200
Vapor Pressure: 1 mmHg (195 °C)
Assay: ≥98%
Form: powder or crystals (with a top layer of Liquid)
Contains: ≥35% water
Expl. Lim.: 0.01 %
Concentration: ≥50-<70%
Melting Point: 122-123 °C (dried material) (lit.)
Solubility: alcohol: 1 (g/12 mL)(lit.), benzene: 1 g/10 mL, chloroform: 1 (g/35 mL), diethyl ether: 1 (g/65 mL)
Density: 1.763 g/cm3
Functional Group: nitro
SMILES String: Oc1c(cc(cc1[N+]([O-])=O)[N+]([O-])=O)[N+]([O-])=O
InChI: 1S/C6H3N3O7/c10-6-4(8(13)14)1-3(7(11)12)2-5(6)9(15)16/h1-2,10H
InChI Key: OXNIZHLAWKMVMX-UHFFFAOYSA-N

Molecular Weight: 229.10 g/mol
XLogP3: 0.9
Hydrogen Bond Donor Count: 1
Hydrogen Bond Acceptor Count: 7
Rotatable Bond Count: 0
Exact Mass: 228.99709944 Da
Monoisotopic Mass: 228.99709944 Da
Topological Polar Surface Area: 158 Ų
Heavy Atom Count: 16
Formal Charge: 0
Complexity: 292
Isotope Atom Count: 0
Defined Atom Stereocenter Count: 0
Undefined Atom Stereocenter Count: 0
Defined Bond Stereocenter Count: 0
Undefined Bond Stereocenter Count: 0
Covalently-Bonded Unit Count: 1
Compound Is Canonicalized: Yes

Physical State at 20 °C: Solid
Colour: Yellow Crystals
Odour: Odorless
Melting Point / Freezing Point [°C]: 121 - 123 °C
Auto-Ignition Temperature [°C]: 300°C
Flash Point [°C]: 150 °C
Vapour Density: 7.9
Density [g/cm3]: 1.763
Solubility in Water [% weight]: Soluble in water
Partition Coefficient Log Pow Octanol / Water at 20°C: 1.33

Specifications of Picric Acid:
Appearance: Yellow crystals
Assay (acidimetric): Min 99.8%
Substance Insoluble in Toluene: Max 0.1%
Melting Point: 120 - 122 deg C
Chloride (Cl): Max 0.0005%
Sulphate (SO4): Max 0.005%
Sulphated Ash: Max 0.02%

Structure of Picric Acid:
Crystal Structure: Orthorhombic
Space Group: Pca21
Lattice Constant: a = 9.2596 Å, b = 19.138 Å, c = 9.7075 Å
Lattice Constant: α = 90°, β = 90°, γ = 90°
Lattice Volume (V): 1720.3 Å3
Formula Units (Z): 8

Thermochemistry of Picric Acid:
Std Enthalpy of Formation (ΔfH⦵298): −215 kJ/mol
Enthalpy of Fusion (ΔfH⦵fus): 20 kJ/mol
Enthalpy of Vaporization (ΔfHvap): 88 kJ/mol

Names of Picric Acid:

Preferred IUPAC name:
2,4,6-Trinitrophenol

Systematic IUPAC name:
2,4,6-Trinitrobenzenol

Other names:
Picric acid
Carbazotic acid
Phenol trinitrate
Picronitric acid
Trinitrophenol
2,4,6-Trinitro-1-phenol
2-Hydroxy-1,3,5-trinitrobenzene
TNP
Melinite
Lyddite