Question

Match metal ion (Part I) with colour (Part II) in presence of alizarin:

	Part I		Part II
I.	$S{n^{2 + }}$	A.	Blue
II.	$M{g^{2 + }}$	B.	Pink
III.	$A{l^{3 + }}$	C.	Violet
IV.	$B{a^{2 + }}$	D.	Red

A. I-A II-D III-C IV-B
B. I-B II-A III-D IV-C
C. I-C II-B III-A IV-D
D. I-D II-C III-B IV-A

Answer 1

Hint: To answer this question, you must recall the colors shown by the metals with alizarin. Alizarin is a mordant dye. Mordant dyes are substances that are used to dye fabrics by forming a coordination bond with them.

Complete step by step solution:
Mordant is a substance that is used in combination with a dye to carry out the dyeing process. It may be used for either dyeing of fabrics or for the intensification of stains in cells and tissues. A mordant is the reason behind the formation of the coordination bond that attaches the dye to the fabrics. It is mostly a polyvalent metal ion that forms the bond. The coordination complex that is formed by the mordant with the dye is colloidal.

The colours shown by alizarin with different metal ions are as follows:
- With aluminium ion it shows red colour
- With tin ion it shows pink colour
- With barium ion it shows violet colour
- With magnesium ion it shows blue colour
The correct matching is given as I-B II-A III-D IV-C

Thus, the correct answer is B.

Note: Alizarin is used in biochemical assay for the quantitative determination of the presence of calcific deposition by the cells of an osteogenic lineage by colorimetry. It is used to stain synovial fluid while testing it for the presence of basic calcium phosphate crystals. It also has various applications in the field of geology where it is used to indicate the minerals of calcium carbonate, like calcite and aragonite.