Chromic acid

Overview IFRA Request a quote

  • Identifiers

    CAS number
    7738-94-5

    Molecular formula
    CrH2O4

    SMILES
    O[Cr](=O)(=O)O

    Safety labels

    Oxidizer
    Oxidizer

    Corrosive
    Corrosive

    Acute Toxic
    Acute Toxic

    Irritant
    Irritant

    Health Hazard
    Health

    Environmental Hazard
    Environmental

  • Odor profile

    Fragrance
    Odorless 90.23%
    Sour 29.5%
    Sharp 19.12%
    Clean 14.2%
    Pungent 13.71%
    Burnt 12.18%
    Cheesy 9.37%
    Sweaty 9.2%
    Cooked 8.96%
    Ethereal 8.89%

     

  • Properties

    pKa est.
    -1.64 (strong acid)

    Molecular weight
    118.01 g/mol

    Melting point expt.

    • 196 °C /Anhydrous chromic acid/

    Boiling point

    • Decomposes at about 250 °C /Anhydrous chromic acid, chromic trioxide/

    Flash point

    • 73.6 ˚C est.

    Solubility expt.

    • In water, 1.1X10+6 mg/L at 17 °C
    • In water, 169 g/100 g water at 25 °C /Anhydrous chromic acid, chromic trioxide/
    • In water, 1854 g/L at 20 °C
    • Soluble in alcohol and mineral acids /Anhydrous chromic acid/
    • For more Solubility (Complete) data for CHROMIC ACID (6 total), please visit the HSDB record page.

  • Synonyms

    • CHROMIC ACID
    • Chromic(VI) acid
    • 7738-94-5
    • dihydroxy(dioxo)chromium
    • Acide chromique
    • Caswell No. 221
    • Chromic acid (H2CrO4)
    • tetraoxochromic acid
    • CCRIS 8994
    • HSDB 6769
    • UNII-SA8VOV0V7Q
    • SA8VOV0V7Q
    • EINECS 231-801-5
    • EPA Pesticide Chemical Code 021101
    • AI3-51760
    • dihydroxidodioxidochromium
    • dihydrogen(tetraaoxidochromate)
    • DTXSID8034455
    • CHEBI:33143
    • J34.508C
    • CHROMIUM HYDROXIDE OXIDE (CR(OH)2O2)
    • (CrO2(OH)2)
    • [CrO2(OH)2]
    • Acide chromique [French]
    • Chromium hydrogen oxide
    • Pesticide Code: 021101
    • DTXCID6014455
    • AKOS025243247
    • NS00093462
    • Q422642
    • 231-801-5

  • Applications

    Chromic acid (CAS 7738-94-5) is primarily used as a strong oxidizing agent in organic synthesis and industrial chemistry, notably for oxidation of primary and secondary alcohols to aldehydes and ketones (Jones-type oxidation). In metal finishing and surface pretreatment, it is used in cleaning and activation baths and as part of chromate conversion coatings to improve corrosion resistance and adhesion of coatings and paints on steel and aluminum. It also serves as a cleaning agent for metal parts, equipment, and laboratory glassware, and plays a role in pretreatment steps that prepare surfaces for subsequent coating or plating. Additionally, chromic acid solutions are involved in coating-related applications to enhance durability of surfaces, subject to safety and regulatory constraints.

    gpt-5-nano

  • Solubility @25˚C

    Solvent Solubility (g/L)
    ethanol 427.79
    methanol 844.85
    isopropanol 299.05
    water 1092.38
    ethyl acetate 37.68
    n-propanol 245.37
    acetone 242.02
    n-butanol 156.03
    acetonitrile 121.19
    DMF 860.11
    toluene 14.24
    isobutanol 134.12
    1,4-dioxane 142.97
    methyl acetate 68.08
    THF 279.64
    2-butanone 85.01
    n-pentanol 103.04
    sec-butanol 146.26
    n-hexane 16.54
    ethylene glycol 563.49
    NMP 307.61
    cyclohexane 19.25
    DMSO 831.66
    n-butyl acetate 30.83
    n-octanol 46.28
    chloroform 27.21
    n-propyl acetate 38.02
    acetic acid 193.44
    dichloromethane 43.52
    cyclohexanone 65.26
    propylene glycol 341.44
    isopropyl acetate 28.37
    DMAc 397.43
    2-ethoxyethanol 272.19
    isopentanol 89.62
    n-heptane 17.99
    ethyl formate 73.91
    1,2-dichloroethane 48.52
    n-hexanol 78.87
    2-methoxyethanol 538.63
    isobutyl acetate 19.6
    tetrachloromethane 11.32
    n-pentyl acetate 27.08
    transcutol 184.61
    n-heptanol 53.27
    ethylbenzene 9.15
    MIBK 40.42
    2-propoxyethanol 206.58
    tert-butanol 203.49
    MTBE 51.58
    2-butoxyethanol 121.69
    propionic acid 119.38
    o-xylene 15.73
    formic acid 422.88
    diethyl ether 88.04
    m-xylene 14.05
    p-xylene 10.09
    chlorobenzene 9.04
    dimethyl carbonate 73.01
    n-octane 7.0
    formamide 562.04
    cyclopentanone 121.66
    2-pentanone 67.44
    anisole 30.5
    cyclopentyl methyl ether 84.62
    gamma-butyrolactone 118.58
    1-methoxy-2-propanol 341.3
    pyridine 65.51
    3-pentanone 50.58
    furfural 123.05
    n-dodecane 4.75
    diethylene glycol 298.71
    diisopropyl ether 23.52
    tert-amyl alcohol 104.05
    acetylacetone 63.77
    n-hexadecane 4.85
    acetophenone 33.51
    methyl propionate 65.14
    isopentyl acetate 20.79
    trichloroethylene 33.85
    n-nonanol 39.17
    cyclohexanol 77.65
    benzyl alcohol 48.49
    2-ethylhexanol 30.42
    isooctanol 32.14
    dipropyl ether 52.88
    1,2-dichlorobenzene 9.39
    ethyl lactate 58.13
    propylene carbonate 47.68
    n-methylformamide 429.25
    2-pentanol 97.44
    n-pentane 28.63
    1-propoxy-2-propanol 128.0
    1-methoxy-2-propyl acetate 44.72
    2-(2-methoxypropoxy) propanol 75.75
    mesitylene 11.81
    ε-caprolactone 53.73
    p-cymene 10.1
    epichlorohydrin 106.75
    1,1,1-trichloroethane 16.48
    2-aminoethanol 514.64
    morpholine-4-carbaldehyde 271.82
    sulfolane 171.24
    2,2,4-trimethylpentane 5.67
    2-methyltetrahydrofuran 95.26
    n-hexyl acetate 30.12
    isooctane 5.63
    2-(2-butoxyethoxy)ethanol 110.89
    sec-butyl acetate 18.65
    tert-butyl acetate 29.73
    decalin 4.87
    glycerin 453.01
    diglyme 182.34
    acrylic acid 130.13
    isopropyl myristate 16.75
    n-butyric acid 75.3
    acetyl acetate 22.71
    di(2-ethylhexyl) phthalate 21.19
    ethyl propionate 34.76
    nitromethane 237.01
    1,2-diethoxyethane 52.95
    benzonitrile 23.92
    trioctyl phosphate 20.89
    1-bromopropane 30.19
    gamma-valerolactone 146.18
    n-decanol 31.51
    triethyl phosphate 22.0
    4-methyl-2-pentanol 43.96
    propionitrile 70.64
    vinylene carbonate 44.64
    1,1,2-trichlorotrifluoroethane 117.27
    DMS 27.86
    cumene 8.72
    2-octanol 33.55
    2-hexanone 42.16
    octyl acetate 24.14
    limonene 13.66
    1,2-dimethoxyethane 264.64
    ethyl orthosilicate 21.37
    tributyl phosphate 19.95
    diacetone alcohol 77.83
    N,N-dimethylaniline 41.18
    acrylonitrile 94.2
    aniline 42.3
    1,3-propanediol 335.33
    bromobenzene 6.15
    dibromomethane 32.58
    1,1,2,2-tetrachloroethane 37.9
    2-methyl-cyclohexyl acetate 21.67
    tetrabutyl urea 38.63
    diisobutyl methanol 21.09
    2-phenylethanol 42.34
    styrene 10.36
    dioctyl adipate 25.63
    dimethyl sulfate 119.51
    ethyl butyrate 29.76
    methyl lactate 111.99
    butyl lactate 42.86
    diethyl carbonate 21.42
    propanediol butyl ether 107.64
    triethyl orthoformate 28.42
    p-tert-butyltoluene 11.06
    methyl 4-tert-butylbenzoate 42.8
    morpholine 211.18
    tert-butylamine 125.55
    n-dodecanol 25.97
    dimethoxymethane 384.48
    ethylene carbonate 41.57
    cyrene 83.4
    2-ethoxyethyl acetate 33.9
    2-ethylhexyl acetate 16.54
    1,2,4-trichlorobenzene 11.46
    4-methylpyridine 45.4
    dibutyl ether 24.49
    2,6-dimethyl-4-heptanol 21.09
    DEF 115.12
    dimethyl isosorbide 94.62
    tetrachloroethylene 32.57
    eugenol 65.24
    triacetin 34.94
    span 80 69.81
    1,4-butanediol 193.86
    1,1-dichloroethane 29.13
    2-methyl-1-pentanol 51.26
    methyl formate 267.19
    2-methyl-1-butanol 84.61
    n-decane 6.75
    butyronitrile 59.01
    3,7-dimethyl-1-octanol 26.25
    1-chlorooctane 14.03
    1-chlorotetradecane 7.61
    n-nonane 7.12
    undecane 5.47
    tert-butylcyclohexane 4.35
    cyclooctane 9.32
    cyclopentanol 138.92
    tetrahydropyran 88.52
    tert-amyl methyl ether 42.62
    2,5,8-trioxanonane 139.86
    1-hexene 26.03
    2-isopropoxyethanol 138.76
    2,2,2-trifluoroethanol 134.41
    methyl butyrate 45.87

    Scent© AI

1 4

IFRA standard 51

Recommendation
No restriction
Maximum acceptable concentrations in the finished product (%)
Category 1
Products applied to the lips
 No restriction Category 7A
Rinse-off products applied to the hair with some hand contact
 No restriction
Category 2
Products applied to the axillae
 No restriction Category 7B
Leave-on products applied to the hair with some hand contact
 No restriction
Category 3
Products applied to the face/body using fingertips
 No restriction Category 8
Products with significant anogenital exposure
 No restriction
Category 4
Products related to fine fragrance
 No restriction Category 9
Products with body and hand exposure, primarily rinse off
 No restriction
Category 5A
Body lotion products applied to the body using the hands (palms), primarily leave on
 No restriction Category 10A
Household care products with mostly hand contact
 No restriction
Category 5B
Face moisturizer products applied to the face using the hands (palms), primarily leave on
 No restriction Category 10B
Household care products with mostly hand contact, including aerosol/spray products (with potential leave-on skin contact)
 No restriction
Category 5C
Hand cream products applied to the hands using the hands (palms), primarily leave on
 No restriction Category 11A
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate without UV exposure
 No restriction
Category 5D
Baby Creams, baby Oils and baby talc
 No restriction Category 11B
Products with intended skin contact but minimal transfer of fragrance to skin from inert substrate with potential UV exposure
 No restriction
Category 6
Products with oral and lip exposure
 No restriction Category 12
Products not intended for direct skin contact, minimal or insignificant transfer to skin
 No restriction