PRODUCTS

HYDROQUINONE (BENZENE-1,4-DIOL)

Hydroquinone (benzene-1,4-diol) is used as a developing agent in photography and as an antioxidant in rubber and food.
Hydroquinone (benzene-1,4-diol) is used as a topical treatment for skin hyperpigmentation and in various cosmetic products.
Hydroquinone (benzene-1,4-diol) is commonly used as a biomarker for benzene exposure.

CAS Number: 123-31-9
EC Number: 204-617-8
MDL number: MFCD00002339
Molecular Formula: C6H6O2 / C6H4-1,4-(OH)2 / C6H4(OH)2
Molar Mass: 110.11 g/mol

SYNONYMS:
Hydroquinone, Idrochinone, Quinol, 1,4-Dihydroxybenzene, p-dihydroxybenzene, 1,4-Hydroxy benzene, 1,4-Benzenediol, HQ, 1,4-Dihydroxybenzene, Hydroquinone, Quinol, P-Hydroquinone, Hydrochinon, Dihydroquinone, Hydroquinol, Benzoquinol, Hydrochinone, Hidroquinone, Hidroquin, Idrochinone, Para-Hydroquinone, Hydroquinole, Hidroquilaude, 1, 4-Dihydroxy-Benzeen, 1, 4-Diidrobenzene, Pyrogentistic Acid, Hydroquinoue, Ccris 714, Diak 5, 1,4-Benzenediol, 1,4-Dihydroxybenzene, 4-Hydroxyphenol, Benzene-1,4-diol, Eldoquin, Hydroquinone, hydroquinone, p-Benzenediol, p-Hydroquinone, p-hydroxyphenol, Quinol, 1,4-benzenediol, benzene-1,4-diol, p-dihydroxybenzene, 1,4-dihydroxybenzene, hydroquinol, p-hydroquinone, hydroquinone, 123-31-9, Benzene-1,4-diol, 1,4-benzenediol, Quinol, 1,4-Dihydroxybenzene, p-Benzenediol, p-Hydroquinone, Dihydroquinone, 1,4-Dihydroxybenzene, Quinol, 1,4-benzenediol, p Benzendiol, Benzoquinol, para-Hydroxyphenol, Dihydroxybenzene, 1,4-Hydroxybenzene, p-Hydroquinone, p-Dihydroxybenzene, 1,4-Benzendil, Aida, Black and White Bleaching Cream, Eldoquin, Elopaque, quinnone, Tecquinol, Hydroquinol, p-Diphenol, Hydrochinon, hydrokinone, p-benzenediol, p-dioxobenzene, alpha-hydroquinone, benzohydroquinone, beta-quinol, arctuvin, eldopaque, tenox hq, tequinol, Benzene-1,4-diol, HQ, 1,4-Benzenediol, p-Benzenediol, p-Dihydroxybenzene, p-Dioxybenzene, p-Hydroquinone, p-Hydroxyphenol, Arctuvin, Benzohydroquinone, Benzoquinol, Diak 5, Eldopaque, Eldoquin, Hidroquinone, Hydroquinol, HE 5, Phiaquin, Quinol, Tecquinol, Tenox HQ, 1,4-Dihydroxybenzene, 4-Hydroxyphenol, p-Dioxobenzene, Hydrochinone, Benzene, p-dihydroxy-, Black and White Bleaching Cream, Derma-Blanch, Hydrochinon, Hydroquinole, Idrochinone, NCI-C55834, Tequinol, USAF EK-356, 1,4-Dihydroxy-benzeen, 1,4-Dihydroxy-benzol, 1,4-Dihydroxybenzen, 1,4-Diidrobenzene, UN 2662, Dihydroquinone, Aida, Eldopacque, Eldopaque forte, Eldoquin forte, Solaquin forte, p-Dihydroquinone, Black & White Bleaching Cream, 1,4-Benzenediol (hydroquinone), Artra (Salt/Mix) p-Hydroxyphenol, 4-Hydroxyphenol, p-Dihydroxybenzene, Benzoquinol, hydroquinol, Dihydroquinone, Eldoquin, p-Dioxybenzene, Solaquin forte, Eldopaque, Hydroquinole, Idrochinone, Tecquinol, Phiaquin, Benzohydroquinone, Hidroquinone, Arctuvin, Tequinol, Dihydroxybenzene, Eldopaque Forte, Eldoquin Forte, Hydrochinon, Tenox HQ, Diak 5, Benzene, p-dihydroxy-, Hydrochinone, 1,4-Dihydroxy-benzol, Artra, Usaf ek-356, 1,4-Diidrobenzene, p-Dioxobenzene, 1,4-Dihydroxybenzen, para-Dioxybenzene, para-Hydroquinone, NCI-C55834, para-Dihydroxybenzene, beta-quinol, HE 5, Pyrogentistic acid, Epiquin, Melanex, Sunvanish, p-Dihydroquinone, alpha-hydroquinone, CHEBI:17594, NSC 9247, HSDB 577, DTXSID7020716, AI3-00072, CHEMBL537, UNII-XV74C1N1AE, NSC-9247, EINECS 204-617-8, XV74C1N1AE, UN2662, Hydroquinone (USP), Hydroquinone [USP], MFCD00002339, HQ, DTXCID70716, NSC9247, EC 204-617-8, Hydroquinone, TRI-LUMA COMPONENT HYDROQUINONE, NCGC00015523-02, quinnone, Eldopacque, p-Phenylenediol, p Benzendiol, p-Quinol, 1,4-Benzoquinol, CAS-123-31-9, SMR000059154, 1,4-Hydroxybenzene, SR-01000075920, 4-DIHYDROXYBENZENE, hydroquinon, BQ(H), Hydroquinoue, Balancer, MedisilkeNight, Supermax, hydroq uinone, hydroquinone gr, MiracleFade, Reduced quinone, a-Hydroquinone, Hydroquinone gel, Idole Carrot, Movate Carrot, Movate Lemon, p-Hydroxybenzene, Scarlight Md, b-Quinol, Caro Light, Hot Movate, Idole Black, 4-Benzenediol, Hydroquinone 4%, 1,4 benzenediol, Clarite 4, Hydro-Q, Obagi-C, Active 4, Hydroquinone,(S), p-dihydroxy benzene, PLQ, HQLA, HYDROP, 4-hydroxyphenyl alcohol, Spectrum_001757, Lopac-H-9003, HYDROQUINONE 8%., WLN: QR DQ, bmse000293, Sh18, Lopac0_000577, SCHEMBL15516, BSPBio_002291, KBioGR_001246, KBioSS_002237, 1,4-Dihydroxybenzene, XIII, MLS000069815, MLS001074911, HYDROQUINONE [WHO-DD], Hydroquinone, LR, >=99%, SPECTRUM1504237, s4580, AKOS000119003, Tox21_110169_1, AM10548, DB09526, LP00577, NSC-758707, RP10102, SDCCGSBI-0050559.P003, UN 2662, BP-21160, EU-0100577, FT-0606877, EN300-18053, C00530, D00073, H 9003, AB00053361_08, Q419164, J-004910, J-521469, SR-01000075920-1, SR-01000075920-4, Q27102742, Z57127551, F1908-0167, Benzene-1,4-diol, Hydroquinone, Idrochinone, Quinol, 1,4-Dihydroxybenzene, p-dihydroxybenzene, p-hydroxyphenol, 1,4-Hydroxy benzene, Calcium Dobesilate Monohydrate Imp. 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Hydroquinone (benzene-1,4-diol), also benzene-1,4-diol or quinol, is an aromatic organic compound which is a type of phenol, having the chemical formula C6H4(OH)2.
Hydroquinone (benzene-1,4-diol)'s chemical structure, shown in the table at right, has two hydroxyl groups bonded to a benzene ring in a para position.

Hydroquinone (benzene-1,4-diol) is a white granular solid at room temperature and pressure.
Hydroquinone (benzene-1,4-diol) is thought to be the active toxin in Agaricus hondensis mushrooms.
Hydroquinone (benzene-1,4-diol) has been shown to be one of the chemical constituents of the natural product propolis.

Hydroquinone (benzene-1,4-diol) is also one of the chemical compounds found in castoreum.
This compound is gathered from the beaver's castor sacs.
Hydroquinone (benzene-1,4-diol), also benzene-1,4-diol, is an aromatic organic compound which is a type of phenol, having the chemical formula C6H4(OH)2.

Hydroquinone (benzene-1,4-diol)'s chemical structure has two hydroxyl groups bonded to a benzene ring in a para position.
Hydroquinone (benzene-1,4-diol) is a white granular solid at room temperature and pressure.
The hydroxyl groups of Hydroquinone (benzene-1,4-diol) are quite weakly acidic.

Hydroquinone (benzene-1,4-diol) can lose an H+ from one of the hydroxyls to form a monophenolate ion or lose an H+ from both to form a diphenolate ion.
Hydroquinone (benzene-1,4-diol) is a major component in most photographic developers where, with the compound Metol, it reduces silver halides to elemental silver.

Hydroquinone (benzene-1,4-diol) is found in many foods, some of which are kai-lan, agar, red bell pepper, and jostaberry.
Hydroquinone (benzene-1,4-diol) belongs to the class of organic compounds known as hydroquinones.
Hydroquinone (benzene-1,4-diol)s are compounds containing a hydroquinone moiety, which consists of a benzene ring with a hydroxyl groups at positions 1 and 4.

Hydroquinone (benzene-1,4-diol) is typically a white granular solid.
Hydroquinone (benzene-1,4-diol) is crystalline in nature, often appearing as small needle-like crystals.

Its pure form is colorless, but Hydroquinone (benzene-1,4-diol) can appear light gray or brownish if impurities are present.
When exposed to light and air, Hydroquinone (benzene-1,4-diol) can become discolored.

Hydroquinone (benzene-1,4-diol), also benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, a derivative of benzene, having the chemical formula C6H4(OH)2.
Hydroquinone (benzene-1,4-diol) is used route is similar to the cumene process in reaction mechanism and involves the dialkylation of benzene with propene to give 1,4-diisopropylbenzene.

Hydroquinone (benzene-1,4-diol) reacts with air to afford the bis(hydroperoxide), which is structurally similar to cumene hydroperoxide and rearranges in acid to give acetone and hydroquinone.
Hydroquinone (benzene-1,4-diol) is herbicide quinhorin, pyrifos grass ling, thiazole grass ling, oxazole grass ling, flupyrifos grass ling, teflon grass ling intermediates, medicine and dye intermediates.

Hydroquinone (benzene-1,4-diol) appears as light colored crystals or solutions.
Hydroquinone (benzene-1,4-diol) is a benzenediol comprising benzene core carrying two hydroxy substituents para to each other.
Hydroquinone (benzene-1,4-diol) is a benzenediol and a member of hydroquinones.

Hydroquinone (benzene-1,4-diol) is safe for use in nail adhesives and in artificial nail coatings, as a polymerization inhibitor, that are cured by LED light.
Hydroquinone (benzene-1,4-diol) is a topical lightening product found in OTC products, and is used to correct skin discoloration associated with disorders of hyperpigmentation including melasma, post-inflammatory hyperpigmention, sunspots, and freckles.

Hydroquinone (benzene-1,4-diol) is a metabolite found in or produced by Escherichia coli.
Hydroquinone (benzene-1,4-diol) is a Melanin Synthesis Inhibitor.
The mechanism of action of Hydroquinone (benzene-1,4-diol) is as a Melanin Synthesis Inhibitor.

The physiologic effect of Hydroquinone (benzene-1,4-diol) is by means of Depigmenting Activity.
Hydroquinone (benzene-1,4-diol) has been reported in Spiranthes vernalis, Phomopsis velata, and other organisms with data available.
Hydroquinone (benzene-1,4-diol) is produced as an inhibitor, an antioxidant, and an intermediate in the synthesis of dyes, motor fuels, and oils; in photographic processing; and naturally in certain plant species.

Hydroquinone (benzene-1,4-diol) is a phenol derivative with antioxidant properties.
Hydroquinone (benzene-1,4-diol) is an aromatic organic compound which is a type of phenol.

Hydroquinone (benzene-1,4-diol) is a small molecule drug with a maximum clinical trial phase of IV (across all indications) that was first approved in 2002 and is indicated for hyperpigmentation of the skin and freckles.
Hydroquinone (benzene-1,4-diol), also known as benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, a derivative of benzene, having the chemical formula C6H4(OH)2.

Hydroquinone (benzene-1,4-diol) has two hydroxyl groups bonded to a benzene ring in a para position.
Hydroquinone (benzene-1,4-diol) is a white granular solid.

Substituted derivatives of this parent compound are also referred to as hydroquinones.
The name "Hydroquinone (benzene-1,4-diol)" was coined by Friedrich Wöhler in 1843.

In 2023, Hydroquinone (benzene-1,4-diol) was the 274th most commonly prescribed medication in the United States, with more than 800,000 prescriptions.
Hydroquinone (benzene-1,4-diol) has a variety of uses principally associated with its action as a reducing agent that is soluble in water.

USES and APPLICATIONS of HYDROQUINONE (BENZENE-1,4-DIOL):
Hydroquinone (benzene-1,4-diol) has a variety of uses principally associated with its action as a reducing agent which is soluble in water.
Hydroquinone (benzene-1,4-diol) is a major component in most photographic developers where, with the compound Metol, it reduces silver halides to elemental silver.

In human medicine, Hydroquinone (benzene-1,4-diol) is used as a topical application in skin whitening to reduce the color of skin as it does not have the same predisposition to cause dermatitis as Metol does.
The disodium diphenolate salt of Hydroquinone (benzene-1,4-diol) is used as an alternating comonomer unit in the production of the polymer PEEK.

As a polymerization inhibitor, Hydroquinone (benzene-1,4-diol) prevents polymerization of acrylic acid, methyl methacrylate, etc.
Hydroquinone (benzene-1,4-diol) is also used as a raw material of herbicides, rubber antioxidants and dye stuffs.
Hydroquinone (benzene-1,4-diol) is commonly used as a biomarker for benzene exposure.

The presence of Hydroquinone (benzene-1,4-diol) in normal individuals stems mainly from direct dietary ingestion, catabolism of tyrosine and other substrates by gut bacteria, ingestion of arbutin containing foods, cigarette smoking, and the use of some over-the-counter medicines.
Hydroquinone (benzene-1,4-diol) has a variety of uses principally associated with its action as a reducing agent which is soluble in water.

Hydroquinone (benzene-1,4-diol) can be used alone, but is more frequently found in combination with other agents such as alpha-hydroxy acids, corticosteroids, retinoids, or sunscreen.
Hydroquinone (benzene-1,4-diol) is used as a developing agent in photography and as an antioxidant in rubber and food.

Hydroquinone (benzene-1,4-diol) is used as a topical treatment for skin hyperpigmentation and in various cosmetic products.
Hydroquinone (benzene-1,4-diol) is commonly used as a biomarker for benzene exposure.
The presence of Hydroquinone (benzene-1,4-diol) in normal individuals stems mainly from direct dietary ingestion, catabolism of tyrosine and other substrates by gut bacteria, ingestion of arbutin containing foods, cigarette smoking, and the use of some over-the-counter medicines.

In human medicine, Hydroquinone (benzene-1,4-diol) is used as a topical application in skin whitening to reduce the color of skin.
Hydroquinone (benzene-1,4-diol) is a major component in most black and white photographic developers for film and paper where, with the compound metol, it reduces silver halides to elemental silver.

There are various other uses associated with its reducing power.
As a polymerisation inhibitor, exploiting its antioxidant properties, Hydroquinone (benzene-1,4-diol) prevents polymerization of acrylic acid, methyl methacrylate, cyanoacrylate, and other monomers that are susceptible to radical-initiated polymerization.

By acting as a free radical scavenger, Hydroquinone (benzene-1,4-diol) serves to prolong the shelf life of light-sensitive resins such as preceramic polymers.
Hydroquinone (benzene-1,4-diol) can lose a hydrogen cation from both hydroxyl groups to form a diphenolate ion.

The disodium diphenolate salt of Hydroquinone (benzene-1,4-diol) is used as an alternating comonomer unit in the production of the polymer PEEK.
Hydroquinone (benzene-1,4-diol) is used as a topical application in skin whitening to reduce the color of skin.
Hydroquinone (benzene-1,4-diol) does not have the same predisposition to cause dermatitis as metol does.

COMMENT ON SOLUBILITY of HYDROQUINONE (BENZENE-1,4-DIOL):
Solubility of Hydroquinone (benzene-1,4-diol) (C6H6O2)
Hydroquinone (benzene-1,4-diol), also known as para-dihydroxybenzene, exhibits notable solubility characteristics that are important for various applications in chemistry.

In terms of solubility:
Aqueous Solubility:
Hydroquinone (benzene-1,4-diol) is moderately soluble in water, primarily due to the presence of two hydroxyl (–OH) groups that can form hydrogen bonds with water molecules.

Solvent Compatibility:
Hydroquinone (benzene-1,4-diol) is more soluble in organic solvents, such as ethanol and acetone, because of its relatively hydrophobic benzene ring.

Temperature Dependence:
The solubility of Hydroquinone (benzene-1,4-diol) can increase with temperature, a common behavior expected in many organic compounds, allowing for greater interaction with solvents.
Overall, the solubility of Hydroquinone (benzene-1,4-diol) is defined by a balance between its hydrophilic hydroxyl groups and its hydrophobic aromatic structure, making it versatile for various chemical reactions and syntheses.

As a general guideline, one might say:
"The solubility of a compound can significantly influence Hydroquinone (benzene-1,4-diol)'s reactivity and applicability in different chemical environments."

INTERESTING FACTS of HYDROQUINONE (BENZENE-1,4-DIOL):
Exploring Hydroquinone (benzene-1,4-diol):
The Versatile Compound
Hydroquinone (benzene-1,4-diol), commonly known as hydroquinone, stands out in the world of organic chemistry for its unique structure and diverse applications.
Here are some intriguing facts about Hydroquinone (benzene-1,4-diol):

STRUCTURAL CHARACTERISTICS of HYDROQUINONE (BENZENE-1,4-DIOL):
Hydroquinone (benzene-1,4-diol) is a dihydroxy derivative of benzene, featuring hydroxyl groups at the 1 and 4 positions of the benzene ring, which contributes to its distinctive properties.

*Radical Scavenger:
Due to its ability to donate electrons, Hydroquinone (benzene-1,4-diol) acts as a strong antioxidant, effectively scavenging free radicals.
This property makes Hydroquinone (benzene-1,4-diol) valuable in various biological and industrial contexts.

*Industrial Usage:
Hydroquinone (benzene-1,4-diol) is utilized in the synthesis of important chemicals, including developers in photography and various polymer products, showcasing its versatility.

*Pharmaceutical Applications:
Hydroquinone (benzene-1,4-diol) plays a significant role in the cosmetic industry, where it is used as a skin lightening agent and in formulations for treating hyperpigmentation.

In summary, Hydroquinone (benzene-1,4-diol) is not just another chemical in the vast array of organic compounds; it is a multifunctional substance that remains crucial in both practical applications and ongoing research.

ALTERNATIVE PARENTS of HYDROQUINONE (BENZENE-1,4-DIOL):
*1-hydroxy-2-unsubstituted benzenoids
*Benzene and substituted derivatives
*Organooxygen compounds
*Hydrocarbon derivatives

SUBSTITUENTS of HYDROQUINONE (BENZENE-1,4-DIOL):
*Hydroquinone
*1-hydroxy-2-unsubstituted benzenoid
*Monocyclic benzene moiety
*Organic oxygen compound
*Hydrocarbon derivative
*Organooxygen compound
*Aromatic homomonocyclic compound

NATURAL OCCURRENCES of HYDROQUINONE (BENZENE-1,4-DIOL):
Hydroquinone (benzene-1,4-diol)s are one of the two primary reagents in the defensive glands of bombardier beetles, along with hydrogen peroxide (and perhaps other chemicals, depending on the species), which collect in a reservoir.

The reservoir opens through a muscle-controlled valve onto a thick-walled reaction chamber.
This chamber is lined with cells that secrete catalases and peroxidases.

When the contents of the reservoir are forced into the reaction chamber, the catalases and peroxidases rapidly break down the hydrogen peroxide and catalyze the oxidation of the hydroquinones into p-quinones.
These reactions release free oxygen and generate enough heat to bring the mixture to the boiling point and vaporize about a fifth of it, producing a hot spray from the beetle's abdomen.

NOMENCLATURE of HYDROQUINONE (BENZENE-1,4-DIOL):
Hydroquinone (benzene-1,4-diol) is the name recommended by the International Union of Pure and Applied Chemistry (IUPAC) in its 1993 Recommendations for the Nomenclature of Organic Chemistry.

PROPERTIES of HYDROQUINONE (BENZENE-1,4-DIOL):
Hydroquinone (benzene-1,4-diol) can undergo mild oxidation to convert to the compound parabenzoquinone, C6H4O2, often called p-quinone or simply quinone.
Reduction of quinone reverses this reaction back to Hydroquinone (benzene-1,4-diol).
Some biochemical compounds in nature have this sort of Hydroquinone (benzene-1,4-diol) or quinone section in their structures, such as Coenzyme Q, and can undergo similar redox interconversions.

The hydroxyl groups of hydroquinone are quite weakly acidic.
Hydroquinone (benzene-1,4-diol) can lose an H+ from one of the hydroxyls to form a monophenolate ion or lose an H+ from both to form a diphenolate ion.

PRODUCTION of HYDROQUINONE (BENZENE-1,4-DIOL):
Hydroquinone (benzene-1,4-diol) is produced industrially in two main ways.
The most widely used route is similar to the cumene process in reaction mechanism and involves the dialkylation of benzene with propene to give 1,4-diisopropylbenzene.

The conversion uses hydrogen peroxide and affords a mixture of Hydroquinone (benzene-1,4-diol) and its ortho isomer catechol (benzene-1,2-diol):
C6H5OH + H2O2 → C6H4(OH)2 + H2O

Other, less common methods include:
A potentially significant synthesis of Hydroquinone (benzene-1,4-diol) from acetylene and iron pentacarbonyl has been proposed.
Iron pentacarbonyl serves as a catalyst, rather than as a reagent, in the presence of free carbon monoxide gas.

Rhodium or ruthenium can substitute for iron as the catalyst with favorable chemical yields but are not typically used due to their cost of recovery from the reaction mixture.
Hydroquinone (benzene-1,4-diol) and its derivatives can also be prepared by oxidation of various phenols, such as aniline and DIPB.

Examples include Elbs persulfate oxidation and Dakin oxidation.
Hydroquinone (benzene-1,4-diol) was first obtained in 1820 by the French chemists Pelletier and Caventou via the dry distillation of quinic acid.

Hydrolysis of chlorophenol.
The latter three methods are generally less atom-economical than oxidation with hydrogen peroxide, and their commercial practice in China produced serious pollution in 2022.

REACTIONS of HYDROQUINONE (BENZENE-1,4-DIOL):
The reactivity of Hydroquinone (benzene-1,4-diol)'s hydroxyl groups resembles that of other phenols, being weakly acidic.
The resulting conjugate base easily undergoes O-alkylation to give mono- and diethers.
Similarly, Hydroquinone (benzene-1,4-diol) is highly susceptible to ring substitution via Friedel–Crafts alkylation.

This reaction is often used for the production of several popular antioxidants, namely 2-tert-butyl-4-methoxyphenol (BHA).
The useful dye quinizarin is produced by diacylation of Hydroquinone (benzene-1,4-diol) with phthalic anhydride.

Redox
Hydroquinone (benzene-1,4-diol) can be reversibly oxidised under mild conditions to give benzoquinone.
Naturally occurring Hydroquinone (benzene-1,4-diol) derivatives, such as coenzyme Q, exhibit similar reactivity, wherein one hydroxyl group is exchanged for an amino group.

Given the conditional reversibility and relative ubiquity of reagents, oxidation reactions of hydroquinones and Hydroquinone (benzene-1,4-diol) derivatives are of significant commercial use, often used at an industrial scale.

When colorless Hydroquinone (benzene-1,4-diol) and benzoquinone - bright yellow in solid form - are cocrystallized at a 1:1 ratio, a dark-green crystalline charge-transfer complex (melting point 171 °C), known as quinhydrone (C6H6O2•C6H4O2), is formed.
This complex dissolves in hot water, dissociating both quinone molecules in solution.

Amination
An important reaction involves the conversion of Hydroquinone (benzene-1,4-diol) to its mono- and di-amine derivatives.
One such derivative, methylaminophenol, used in photography, is produced according to the stochiometry:
C6H4(OH)2 + CH3NH2 → HOC6H4NHCH3 + H2O

Diamines - used in the rubber industry as antiozone agents - aminated from aniline, are formed via a similar pathway:
C6H4(OH)2 + 2 C6H5NH2 → C6H4(N(H)C6H5)2 + 2 H2O

PHYSICAL and CHEMICAL PROPERTIES of HYDROQUINONE (BENZENE-1,4-DIOL):
CAS number: 123-31-9
EC index number: 604-005-00-4
EC number: 204-617-8
Hill Formula: C₆H₆O₂
Chemical formula: C₆H₄(OH)₂
Molar Mass: 110.11 g/mol
HS Code: 2907 22 00
Boiling point: 287 °C (1013 hPa)
Density: 1.332 g/cm3 (15 °C)
Flash point: 165 °C
Ignition temperature: 515 °C
Melting Point: 171 °C (decomposition)

pH value: 3.7 (70 g/l, H₂O)
Vapor pressure: 1 hPa (132 °C)
Bulk density: 600 kg/m3
Solubility: 70 g/l
Chemical Name: HYDROQUINONE
CAS No: 123-31-9
Main Material: HYDROQUINONE
Storage: Other
Boiling point: 287 °C (549 F; 560 K)
HS Code: 29072200

Grade: Industrial Grade
Taste: Other
Molecular Weight: 110.112 g/mol
Molecular Formula: 110.112 g/mol
Classification: Other
Smell: Other
Other Names: Quinol
Density: 1.3 g/cm3, solid Kilogram per litre (kg/L)
Melting Point: 172 °C (342 F; 445 K)
Solubility: 5.9 g/100 mL (15 °C)
Structural Formula: C6H6O2

Form: Solid
CAS: 123-31-9
EINECS: 204-617-8
InChI: InChI=1/C9H6O4/c10-6-3-5-1-2-9(12)13-8(5)4-7(6)11/h1-4,10-11H
InChIKey: QIGBRXMKCJKVMJ-UHFFFAOYSA-N
Molecular Formula: C6H6O2
Molar Mass: 110.11
Density: 1.32
Melting Point: 172-175°C (lit.)
Boiling Point: 285°C (lit.)
Flash Point: 165 °C

Water Solubility: 70 g/L (20 ºC)
Solubility: H2O: 50 mg/mL, clear
Vapor Pressure: 1 mm Hg (132 °C)
Vapor Density: 3.81 (vs air)
Appearance: Needle-Like Crystals or Crystalline Powder
Color: White to off-white
Merck: 14,4808
BRN: 605970
pKa: 10.35 (at 20°C)
Storage Condition: Store below +30°C.

Stability: Stable.
Sensitive: Air & Light Sensitive
Refractive Index: 1.6320
Molecular Weight: 110.11
Appearance Form: crystalline
Color: colorless
Odor: No data available
Odor Threshold: No data available
pH: 3,7 at 70 g/l

Melting point/freezing point:
Melting point/range: 172 - 175 °C - lit.
Initial boiling point and boiling range: 285 °C - lit.
Flash point: 165 °C at ca.1.013 hPa
Evaporation rate: No data available
Flammability (solid, gas): The product is not flammable.
Upper/lower flammability or explosive limits: No data available
Vapor pressure: 1 hPa at 132 °C
Vapor density: 3,80 - (Air = 1.0)

Density: 1,332 g/cm3 at 15 °C
Relative density: No data available
Water solubility 72 g/l at 25 °C - completely soluble
Partition coefficient: n-octanol/water
log Pow: 0,59 - Bioaccumulation is not expected.
Autoignition temperature: 515,56 °C at 1.013 hPa
Decomposition temperature: No data available
Viscosity
Viscosity, kinematic: No data available
Viscosity, dynamic: No data available

Explosive properties: No data available
Oxidizing properties: No data available
Other safety information:
Relative vapor density: 3,80 - (Air = 1.0)
Water Solubility: 95.5 g/L
logP: 0.71
logP: 1.37
logS: -0.06
pKa (Strongest Acidic): 9.68
pKa (Strongest Basic): -5.9
Physiological Charge: 0

Hydrogen Acceptor Count: 2
Hydrogen Donor Count: 2
Polar Surface Area: 40.46 Å²
Rotatable Bond Count: 0
Refractivity: 30.02 m³·mol⁻¹
Polarizability: 10.75 Å³
Number of Rings: 1
Bioavailability: Yes
Rule of Five: Yes
Ghose Filter: No
Veber's Rule: No
MDDR-like Rule: No
IUPAC Name: benzene-1,4-diol

Traditional IUPAC Name: α-hydroquinone
Formula: C6H6O2
InChI: InChI=1S/C6H6O2/c7-5-1-2-6(8)4-3-5/h1-4,7-8H
InChI Key: QIGBRXMKCJKVMJ-UHFFFAOYSA-N
Molecular weight: 110.1106
Exact mass: 110.036779436
SMILES: OC1=CC=C(O)C=C1
Chemical Formula: C6H6O2
Average Molecular Weight: 110.1106
Monoisotopic Molecular Weight: 110.036779436

IUPAC Name: benzene-1,4-diol
Traditional Name: α-hydroquinone
CAS Registry Number: 123-31-9
SMILES: OC1=CC=C(O)C=C1
InChI Identifier: InChI=1S/C6H6O2/c7-5-1-2-6(8)4-3-5/h1-4,7-8H
InChI Key: QIGBRXMKCJKVMJ-UHFFFAOYSA-N
Melting Point: 170.0°C to 174.0°C
Color: White
Density: 1.32
Boiling Point: 285.0°C to 287.0°C
Flash Point: 165°C

Infrared Spectrum: Authentic
Assay Percent Range: 98.5% min. (HPLC)
Beilstein: 06, 836
Fieser: 05,341; 14,249
Merck Index: 15, 4845
Solubility Information: Solubility in water: 70g/L in water (20°C).
Other solubilities: soluble in alcohol and ether,slightly soluble in benzene,
readily soluble in ethanol,acetone and methanol
Formula Weight: 110.11

Percent Purity: 99%
Physical Form: Needle-like Crystals or Crystalline Powder
Chemical Name or Material: Hydroquinone, 99%
C6H6O2: Hydroquinone
Molecular Weight/ Molar Mass: 110.11 g/mol
Density: 1.3 g cm−3
Boiling Point: 287 °C
Melting Point: 172 °C

FIRST AID MEASURES of HYDROQUINONE (BENZENE-1,4-DIOL):
-Description of first-aid measures:
*General advice:
Show this material safety data sheet to the doctor in attendance.
*If inhaled
After inhalation:
Fresh air.
Call in physician.
*In case of skin contact:
Take off immediately all contaminated clothing.
Rinse skin with water/ shower.
Consult a physician.
*In case of eye contact
After eye contact:
Rinse out with plenty of water.
Immediately call in ophthalmologist.
Remove contact lenses.
*If swallowed:
After swallowing:
Immediately make victim drink water (two glasses at most).
Consult a physician.
-Indication of any immediate medical attention and special treatment needed:
No data available

ACCIDENTAL RELEASE MEASURES of HYDROQUINONE (BENZENE-1,4-DIOL):
-Personal precautions, protective equipment and emergency procedures:
Advice for non-emergency personnel:
Ensure adequate ventilation.
Evacuate the danger area, observe emergency procedures, consult an expert.
-Environmental precautions:
Do not let product enter drains.
-Methods and materials for containment and cleaning up:
Cover drains.
Collect, bind, and pump off spills.
Observe possible material restrictions.
Take up dry.
Dispose of properly.
Clean up affected area.

FIRE FIGHTING MEASURES of HYDROQUINONE (BENZENE-1,4-DIOL):
-Extinguishing media:
*Suitable extinguishing media:
Water Foam Carbon dioxide (CO2)
Dry powder
*Unsuitable extinguishing media:
For this substance/mixture no limitations of extinguishing agents are given.

EXPOSURE CONTROLS/PERSONAL PROTECTION of HYDROQUINONE (BENZENE-1,4-DIOL):
-Control parameters:
--Ingredients with workplace control parameters:
-Exposure controls:
--Personal protective equipment:
*Eye/face protection:
Use safety goggles.
Full contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 480 min
Splash contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 480 min
*Body Protection:
Use protective clothing.
-Control of environmental exposure:
Do not let product enter drains.

HANDLING and STORAGE of HYDROQUINONE (BENZENE-1,4-DIOL):
-Precautions for safe handling:
*Advice on safe handling:
Work under hood.
Do not inhale substance/mixture.
*Hygiene measures:
Wash hands and face after working with substance.
-Conditions for safe storage, including any incompatibilities:
Storage conditions:
Tightly closed.
Dry.

STABILITY and REACTIVITY of HYDROQUINONE (BENZENE-1,4-DIOL):
-Chemical stability
The product is chemically stable under standard ambient conditions (room temperature) .