ferric chloride

chemical compound

Also known as: iron(III) chloride

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June 26, 2026

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Ferric chloride is a dark, deliquescent salt with the chemical formula FeCl₃. It readily hydrates to a yellow-orange form and is used in applications such as etching, sewage treatment, and as an astringent. Ferric chloride is a type of iron chloride, which also includes ferrous chloride (FeCl₂). Iron itself is a metal, the most used and cheapest, making up about 5% of Earth's crust. Iron compounds commonly exist in two oxidation states: +2 (ferrous) and +3 (ferric).123

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chemical compound
Binary ionic compounds
…which contains Fe³⁺, is named iron(III) chloride. On the other hand, the compound FeCl₂, which contains Fe²⁺, is designated as iron(II) chloride. In each case, the Roman numeral in the name specifies the charge of the metal ion present.
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…which contains Fe³⁺, is named iron(III) chloride. On the other hand, the compound FeCl₂, which contains Fe²⁺, is designated as iron(II) chloride. In each case, the Roman numeral in the name specifies the charge of the metal ion present.
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iron
Compounds
Ferric chloride is generally prepared from ferrous chloride through the action of chloride or nitric acid. It is used to make many other ferric compounds and as a chlorinating agent for silver, copper, and some organic compounds. Treating a solution of Fe³⁺ with the complex…
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Ferric chloride is generally prepared from ferrous chloride through the action of chloride or nitric acid. It is used to make many other ferric compounds and as a chlorinating agent for silver, copper, and some organic compounds. Treating a solution of Fe³⁺ with the complex…
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photoengraving
Etching and finishing
…is more readily attacked by ferric chloride (iron chloride), which is commonly used in concentrations of 28–45 percent. The etching may be done in an open tub or tray, though this method does not give the control needed for economical operation and is employed only where control is not critical.…
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…is more readily attacked by ferric chloride (iron chloride), which is commonly used in concentrations of 28–45 percent. The etching may be done in an open tub or tray, though this method does not give the control needed for economical operation and is employed only where control is not critical.…
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