What is the Difference Between Hydrated and Anhydrous Copper Sulphate

The key difference between hydrated and anhydrous copper sulphate is that hydrated copper sulphate appears in a bright blue color, whereas anhydrous copper sulphate appears as a white powder.

Copper sulphate is an inorganic compound having the chemical formula CuSO4. This compound occurs mainly in hydrated forms. Here, the number of water molecules associated with copper sulphate can range from 0 to 5. Moreover, the pentahydrate form is the most common form. The anhydrous form appears as a white powder, but the hydrated forms are bright blue.

CONTENTS

1. Overview and Key Difference
2. What is Hydrated Copper Sulphate
3. What is Anhydrous Copper Sulphate
4. Hydrated vs Anhydrous Copper Sulphate in Tabular Form
5. Summary – Hydrated vs Anhydrous Copper Sulphate

What is Hydrated Copper Sulphate?

Hydrate copper sulphate is an inorganic compound having water molecules associated with copper sulphate molecules. The hydrated copper sulphate appears in a bright blue color. The most common hydrated form is the pentahydrated form. CuSO4 5H2O is copper(II) sulfate pentahydrate. It has five water molecules associated with the copper sulfate molecule. It appears as a bright blue colour solid. Besides, it is the most common hydrated form of copper sulfate. Some common names for this compound are blue vitriol, bluestone, the vitriol of copper, Roman vitriol, etc.

Moreover, this compound exothermally dissolves in water. Then, it forms an aqua complex containing one CuSO4 molecule in association with six water molecules, and this complex has an octahedral molecular geometry. Its molar mass of 249.65 g/mol. When considering the melting point, upon heating above 560 °C, the compound decomposes. That means the compound decomposes before melting. This compound removes two water molecules at 63 °C and two more at 109 °C. Furthermore, the final water molecule is released at 200 °C.

What is Anhydrous Copper Sulphate?

Anhydrous copper sulphate is an inorganic compound having only copper sulphate molecules in its chemical structure. CuSO4 is copper(II) sulfate that has the copper metal in a +2 oxidation state. It is an inorganic compound that has no water molecules associated with it. Therefore, we call it the anhydrous form of copper sulfate. Moreover, this anhydrous compound occurs as a white powder.

The industrial production of copper sulfate involves treating the copper metal with sulfuric acid in hot and concentrated form. It is also possible to produce this compound using oxides of copper. It is done by treating copper oxide with diluted sulfuric acid. In addition, slowly leaching low-grade copper ore in the air is another method of production. It is possible to use bacteria to catalyze this process.

What is the Difference Between Hydrated and Anhydrous Copper Sulphate?

Copper sulphate is an inorganic compound that can be found in two forms; they are the hydrated form and the anhydrous form. The key difference between hydrated and anhydrous copper sulphate is that hydrated copper sulphate appears in a bright blue color, whereas anhydrous copper sulphate appears as a white powder.

The below infographic presents the differences between hydrated and anhydrous copper sulphate in tabular form for side by side comparison.

Summary – Hydrated vs Anhydrous Copper Sulphate

Hydrate copper sulphate is an inorganic compound having water molecules associated with copper sulphate molecules. Anhydrous copper Sulphate is an inorganic compound having only copper sulphate molecules in its chemical structure. The key difference between hydrated and anhydrous copper sulphate is that hydrated copper sulphate appears in a bright blue color whereas anhydrous copper sulphate appears as a white powder.

Reference:

1. “Heating of Copper Sulphate.” Robolab Technologies Pvt. Ltd., 27 May 2019.

Image Courtesy:

1. “Copper sulfate” By Stephanb – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Synthesizing Copper Sulfate” By Dmwdev – Own work (CC BY 3.0) via Commons Wikimedia