Question

Copper sulphate crystals are which color after purification?
A.White
B.Black
C.Blue
D.Yellow

Answer 1

Copper is an essential trace element that is included in some over the counter multivitamin and mineral supplements, even though copper deficiency is quite rare and supplementation is rarely needed. The amount of copper found in typical supplements has not been associated with serum enzyme elevations or with clinically apparent liver injury. It appears as white or off-white solid.

Complete answer:
When copper sulphate dissolved in water and a small quantity of dil. Sulfuric acid which is added to prevent the hydrolysis of copper sulphate. The impurities are removed with the help of filtration. The filtrate is concentrated by the crystallization point and then cooled. After cooling, copper sulphate separated which has transparent blue crystals.
So, copper sulphate crystals are blue after purification.

Hence, option (C) is the correct answer.

Additional information:
Copper sulfate is used as a drying agent in the anhydrous form, as an additive for fertilizers and foods, and several industrial applications such as textiles, leather, wood, batteries, ink, petroleum, paint and metal, among others, it is used also as an animal nutritional supplement.

Note: Crystallization is the process by which we can obtain crystals of copper sulphate. In this process, dilute Sulphuric acid is added to water. Copper sulfate is an algaecide, bactericide, and fungicide. When it is mixed with calcium hydroxide it is known as Bordeaux mixture. It is also a ubiquitous element. It can be found in the environment and water.