ferrous sulfate

chemical compound

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Last updated

July 13, 2026

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Ferrous sulfate is a chemical compound, typically appearing as bluish-green hydrated crystals with the formula FeSO₄·7H₂O. It is a salt derived from iron and sulfuric acid.12

Ferrous sulfate has several uses:
* Medicine: It is used to treat anemia caused by iron deficiency.1
* Industry: It is utilized in the production of inks, pigments, and other iron salts. It also serves as a reducing agent and is employed in fertilizers and pesticides.12

Ferrous sulfate is distinct from ferric sulfate (Fe₂(SO₄)₃), which is used in water purification, as a mordant in dyeing, and in metal pickling. Iron itself is a common metal, essential for life and abundant in Earth's crust and core.32

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The modern inks usually contain ferrous sulfate as the iron salt with a small amount of mineral organic acid. The resulting solution is light bluish black and, if used alone on paper, appears only faintly. After standing it becomes darker and insoluble in water, which gives it a permanent quality.…
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The modern inks usually contain ferrous sulfate as the iron salt with a small amount of mineral organic acid. The resulting solution is light bluish black and, if used alone on paper, appears only faintly. After standing it becomes darker and insoluble in water, which gives it a permanent quality.…
Read More