Cadmium sulfate is the name of a series of related inorganic compound

Inorganic compound

Inorganic compounds have traditionally been considered to be of inanimate, non-biological origin. In contrast, organic compounds have an explicit biological origin. However, over the past century, the classification of inorganic vs organic compounds has become less important to scientists,...

s with the formula

Chemical formula

A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

 CdSO₄.xH₂O. The most common form is the monohydrate CdSO₄.H₂O, but two other forms are known CdSO₄.8/3H₂O and the anhydrous

Anhydrous

As a general term, a substance is said to be anhydrous if it contains no water. The way of achieving the anhydrous form differs from one substance to another...

 salt (CdSO₄). All salts are colourless and highly soluble in water.

Preparation and occurrence

Cadmium sulfate octohydrate can be prepared by the reaction of cadmium metal or its oxide or hydroxide with dilute sulfuric acid:

CdO + H₂SO₄ → CdSO₄ + H₂O

Cd + H₂SO₄ → CdSO₄ + H₂

The anhydrous material is prepared using sodium persulfate

Sodium persulfate

Sodium persulfate is a chemical compound. It is a strong oxidizer. It is a severe irritant of skin, eyes, and respiratory system. It is almost non-hygroscopic and has particularly good ability to be stored for long time. It is easy and safe to handle...

:

Cd + Na₂S₂O₈ → CdSO₄ + Na₂SO₄

Cadmium sulfate is very rarely found naturally in from of a tetrahydrate mineral called drobecite and as a basic salt in the mineral Niedermayrite

Niedermayrite

Niedermayrite is a rare hydrated copper cadmium sulfate hydroxide mineral with formula: Cu4Cd26·4H2O. It crystallizes in the monoclinic system and occurs as encrustations and well formed vitreous blue-green prismatic crystals. It has a specific gravity of 3.36.Niedermayrite was named for Gerhard...

. It is used as a pigment

Pigment

A pigment is a material that changes the color of reflected or transmitted light as the result of wavelength-selective absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which a material emits light.Many materials selectively absorb...

.

Applications

Cadmium sulfate is used widely for the electroplating of cadmium in electronic circuits.
It is also a precursor to cadmium-based pigment such as cadmium sulfide

Cadmium sulfide

Cadmium sulfide is the inorganic compound with the formula CdS. Cadmium sulfide is a yellow solid. It occurs in nature with two different crystal structures as the rare minerals greenockite and hawleyite, but is more prevalent as an impurity substituent in the similarly structured zinc ores...

. It is also used for electrolyte

Electrolyte

In chemistry, an electrolyte is any substance containing free ions that make the substance electrically conductive. The most typical electrolyte is an ionic solution, but molten electrolytes and solid electrolytes are also possible....

 in a Weston standard cell.