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Chromium(II) fluoride

chemical compound

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Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionFeb 6, 2026
Entity authorityQ423577 ↗
Source-derived summary

Chromium(II) fluoride is an inorganic compound with the formula CrF2. It exists as a blue-green iridescent solid. Chromium(II) fluoride is sparingly soluble in water, almost insoluble in alcohol, and is soluble in boiling hydrochloric acid, but is not attacked by hot distilled sulfuric acid or nitric acid. Like other chromous compounds, chromium(II) fluoride is oxidized to chromium(III) oxide in air.

Preparation and structure

The compound is prepared by passing anhydrous hydrogen fluoride over anhydrous chromium(II) chloride. The reaction will proceed at room temperature but is typically heated to 100-200 °C to ensure completion:

CrCl2 + 2 HF → CrF2 + 2 HCl

Like many difluorides, CrF2 adopts a structure like rutile with octahedral molecular geometry about Cr(II) and trigonal geometry at F−. Two of the six Cr–F bonds are long at 2.43 Å, and four are short near 2.00 Å. This distortion is a consequence of the Jahn–Teller effect that arises from the d4 electron configuration of the chromium(II) ion.

Editorial summary

“Chromium(II) fluoride” enters the record as chemical compound. Crown Archives preserves that source wording while asking what Chromium, fluoride and chemical can confirm, complicate or overturn.

Editorial reviewA practical orientation to terminology and classification, particularly when read beside dated observations, specimens or technical literature. The current 160-word lead offers orientation but no explicit four-digit date, so chronology should not be assumed. The selected authority fields contribute no independent date. Its strongest next move is a source search built around Chromium, fluoride and chemical.
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“Chromium(II) fluoride” is worth following because a concise public description often conceals a longer documentary argument. Here, Chromium, fluoride and chemical provides the most credible route into that argument.

Evidence profile

Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Feb 6, 2026. The linked authority identifier is Q423577. None of the 0 selected statements returned an explicit reference.

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A general summary may omit uncertainty, sample limits or methodological disagreement that is explicit in the technical record. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

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This entry incorporates text from “Chromium(II) fluoride” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.