Bluish-green monoclinic crystals or granules, odorless. It effloresces in dry air and oxidizes on the surface to brown basic ferric sulfate in moist air. At 56.6°C, it becomes tetrahydrate, and at 65°C, it becomes monohydrate. Soluble in water, almost insoluble in ethanol. Its aqueous solution oxidizes slowly in air when cold and more rapidly when hot. The addition of alkali or exposure to light accelerates its oxidation. Relative density (d15) 1.897. Irritating. Anhydrous ferrous sulfate is a white powder, while the hydrated form is a light green crystal, commonly known as "green vitriol," and its aqueous solution is light green. Ferrous sulfate can be used as a chromatographic analysis reagent, spot analysis for the determination of selenium, nitrite, and nitrate. It can also serve as a reducing agent, for manufacturing ferrites, water purification, polymerization catalysts, photomechanical printing, etc. Ferrous sulfate is used in the production of iron salts, iron oxide pigments, mordants, water purifiers, preservatives, and agents; Ferrous Sulfate1. Water TreatmentFerrous sulfate is used for the flocculation and purification of water, as well as for the removal of phosphates from municipal and industrial wastewater to prevent eutrophication of water bodies.2. Reducing AgentLarge quantities of ferrous sulfate are used as a reducing agent, primarily to reduce chromates in cement.3. Coloring Agenta. The production of iron gall ink and other inks requires ferrous sulfate. It is also contained in mordants for wood staining. 4. AgricultureIt regulates soil pH and promotes chlorophyll formation (also known as iron fertilizer), preventing chlorosis in flowers and trees caused by iron deficiency. It is an essential element for acid-loving plants, especially cycads. In agriculture, it can also be used as a pesticide to control wheat smut, apple and梨 scab, and fruit tree canker; it can also serve as a fertilizer to remove moss and lichen from tree trunks.5. Analytical ChemistryFerrous sulfate can be used as a chromatographic analysis reagent.In agriculture 

It can be used as a pesticide to control wheat smut, apple and pear scab, and fruit tree canker; food-grade is used as a nutritional supplement, such as an iron fortifier and color fixative for fruits and vegetables. It can also be used as a fertilizer to supplement iron in plants, preventing physiological diseases due to iron deficiency and chlorosis in plant leaves. It can remove moss and lichen from tree trunks. It is a raw material for the production of magnetic iron oxide, iron red and iron blue inorganic pigments, iron catalysts, and polyferric sulfate.