formula for iron ii sulfate heptahydrate
The chemical formula for iron ii sulfate is FeSO4*xH2O, where x is a number that describes the degree of hydration (in water) of this salt. The most common form of iron ii sulfate, or ferrous sulfate, is the blue-green heptahydrate which contains a value of x between seven and nine.
This sulfate is one of several iron compounds in a class known as metal sulfates, which are salts formed by replacing one or more hydrogens in sulfuric acid with a metal ion. They are soluble in water for uses such as aqueous disinfectants, water treatment and corrosion control.
They can also be dissolved in organic solvents for uses such as cosmetics and ointments. They are commonly used in the manufacture of iron compounds and in electroplating baths, aluminum etching, process engraving and lithography, as well as in redox polymerization.
Inks, dyes and reducing agents: Iron(II) sulfate has been in use for centuries as a fixative in dyeing wool. It is also used as a reducing agent in chemical processes and writing inks. In the 17th century it was used to blacken leather and as a component of iron gall ink, which made sharp designs that could not be achieved by other methods.
Another industrial use for iron sulfate is in the production of titanium dioxide from ilmenite through the sulfate process. This sulfate can be deposited on sputtering targets for use as a substrate in solar cells and fuel cells.