Iron(III) oxide-hydroxide
type: Thing
alternate name: hydrous ferric oxide
alternate name: HFO
alternate name: ferrihydrite
description: hydrous ferric oxide (HFO)
additional property: PropertyValue
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  value: type of chemical entity
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  value: O[Fe]=O
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  value: InChI=1S/Fe.H2O.O/h;1H2;/q+1;;/p-1
additional property: PropertyValue
  property ID: P235
  value: AEIXRCIKZIZYPM-UHFFFAOYSA-M
additional property: PropertyValue
  property ID: P274
  value: FeHO₂
additional property: PropertyValue
  property ID: P279
  value: hydroxide salt
additional property: PropertyValue
  property ID: P527
  value: hydrogen
additional property: PropertyValue
  property ID: P527
  value: iron
additional property: PropertyValue
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  value: oxygen
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  value: DTXSID3042057
additional property: PropertyValue
  property ID: P3117
  value: DTXSID801318339
additional property: PropertyValue
  property ID: P4149
  value: iron(III) oxide-hydroxide(1-)
additional property: PropertyValue
  property ID: P4952
  value: NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response
additional property: PropertyValue
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additional property: PropertyValue
  property ID: P6802
  value: Ochra.JPG
additional property: PropertyValue
  property ID: P8072
  value: 158162
additional property: PropertyValue
  property ID: P8224
  value: FeOOH.png
additional property: PropertyValue
  property ID: P8408
  value: FerricHydroxide
confidence:
  popularity graph score:
    score: 0.023
    score pct: 2
    tier: established
    components:
      sitelinks: 26
      sitelinks norm: 0.061
      unique citations: 9
      unique citations norm: 0.004
      monthly pageviews: 0
      monthly pageviews norm: 0.0
  sitelinks: 26
  unique citations: 9
  monthly pageviews: 0
  yearly pageviews: 918
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    v: 489
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  popularity:
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    max: 423
    pct: 6.1
    rank label: top 10%
  tier: established
claims:
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    value: Q113145171
    source count: 0
    confidence: 0.0
    value label: type of chemical entity
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  P235:
    value: AEIXRCIKZIZYPM-UHFFFAOYSA-M
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  P274:
    value: FeHO₂
    source count: 1
    confidence: 0.2
  P279:
    value: Q425597
    source count: 0
    confidence: 0.0
    value label: hydroxide salt
  P527:
    value: Q556
    source count: 0
    confidence: 0.0
    value label: hydrogen
  P527:
    value: Q677
    source count: 0
    confidence: 0.0
    value label: iron

value: Q629
source count: 0
confidence: 0.0
value label: oxygen

value: /m/090_zn
source count: 1
confidence: 0.2

value: 87PZU03K0K
source count: 0
confidence: 0.0

value: 82623
source count: 1
confidence: 0.2

value: 91502
source count: 2
confidence: 0.4

value: 1300
source count: 0
confidence: 0.0

value:
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source count: 1
confidence: 0.2

value: 100.039.754
source count: 1
confidence: 0.2

value: 1639061
source count: 1
confidence: 0.2

value: 345408
source count: 1
confidence: 0.2

value: 34593
source count: 1
confidence: 0.2

value: DTXSID3042057
source count: 1
confidence: 0.2

value: DTXSID801318339
source count: 1
confidence: 0.2

value: Q27147874
source count: 0
confidence: 0.0
value label: iron(III) oxide-hydroxide(1-)

value: Q51139288
source count: 1
confidence: 0.2
value label: NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency Response

value: 2776894444
source count: 0
confidence: 0.0

value: Ochra.JPG
source count: 0
confidence: 0.0

value: 158162
source count: 1
confidence: 0.2

value: FeOOH.png
source count: 0
confidence: 0.0

value: FerricHydroxide
source count: 1
confidence: 0.2

value: DTXCID1022057
source count: 0
confidence: 0.0

value: 22948525
source count: 1
confidence: 0.2

title: Lepidocrocite
source: PubChem
stated in qid: Q278487
retrieved: 2016-09-20

title: Hydroxy(oxo)iron
source: ChemSpider
stated in qid: Q2311683
retrieved: 2016-09-20

title: Iron hydroxide oxide
source: ECHA Substance Infocard database
stated in qid: Q59911453
retrieved: 2018-12-27

title: IRON HYDROXIDE
source: CosIng database
stated in qid: Q26255597
retrieved: 2019-12-28

source: Freebase Data Dumps
stated in qid: Q15241312
pub year: 2013

source: CABI Thesaurus
stated in qid: Q88285346
retrieved: 2020-04-06

source: KBpedia
stated in qid: Q64139102
retrieved: 2020-07-09

source: Mapping file of InChIStrings, InChIKeys and DTXSIDs for the EPA CompTox Dashboard
stated in qid: Q28061352

source: UniChem
stated in qid: Q24170711

wikidata id: Q412739
domain: type_of_chemical_entity
level: standard
html url: https://4ort.xyz/entity/iron-iii-oxide-hydroxide
markdown url: https://4ort.xyz/entity/iron-iii-oxide-hydroxide.md
facts url summary: https://4ort.xyz/entity/iron-iii-oxide-hydroxide/facts.json
facts url standard: https://4ort.xyz/entity/iron-iii-oxide-hydroxide/facts.json
facts url full: https://4ort.xyz/entity/iron-iii-oxide-hydroxide/facts.json
data source: Wikidata (CC0 / public domain)
license: https://creativecommons.org/publicdomain/zero/1.0/
api version: v1
served at: 2026-08-24T09:35:41.458632Z
entity updated at: 2026-05-03T22:54:58.348740+00:00Z
entity created at: 2026-04-10T23:55:43.014265+00:00Z