Question

Alizarin, a mordant dye is not used in:
A. Painting
B. Wool dyeing
C. Printing
D. Cotton dyeing

Answer 1

Hint: We know that Alizarin is a mordant dye which is mainly used in the dyeing purposes. It is also used in hand block printing technique. Based on the different applications of Alizarin we can choose the correct answer.

Complete Step by step answer: Alizarin is an organic compound whose chemical formula is ${C_{14}}{H_8}{O_4}$ (also known as 1,2-dihydroxyanthraquinone), Mordant red 11 that has been used throughout history as a prominent red dye especially for dyeing textile fabrics. Initially, it was derived from the roots of plants of the madder genus. In 1869, it became the first natural dye to be produced synthetically. It is known by different names such as Alizarin B, Alizarin red, Turkey red, etc. It is slightly soluble in water.
The word Alizarin is the most common term for the dye that has deep red colour but it is also used for the several non-red dyes such as Alizarin Cyanine Green and Alizarin Brilliant blue. The most important use of alizarin in modern times is as a staining agent in biological research because it stains free calcium and certain calcium compounds. Alizarin continues to be used commercially as a red textile dye but to a lesser extent than in the past.
A mordant dye is a substance which is used to set or bind dyes on fabrics by forming a coordination complex with the dye that gets attached to the fabric. Alizarin printing is one of the most practised techniques of hand block printing in India. In printing, alizarin is used in the dyeing process.

Therefore, option A is correct.

Note: We should remember that a mordant is a substance which is used for dyeing fabrics or for intensifying stains in cell or tissue preparations and Alizarin is mainly used for dyeing purposes such as wool and cotton dyeing.