Question

When Ethane-1,2-diamine is added progressively to an aqueous solution of Nickel (II) chloride, the sequence of colour change observed will be:

• A. Green \(\rightarrow\) Pale Blue \(\rightarrow\) Blue \(\rightarrow\) Violet
• B. Pale Blue \(\rightarrow\) Blue \(\rightarrow\) Green \(\rightarrow\) Violet
• C. Pale Blue \(\rightarrow\) Blue \(\rightarrow\) Violet \(\rightarrow\) Green
• D. Violet \(\rightarrow\) Blue \(\rightarrow\) Pale Blue \(\rightarrow\) Green

Hint:

The color changes in coordination compounds depend on the nature of ligands and the metal ion.

Answer 1

The Correct Option is C

- As ethane-1,2-diamine is added to the solution, the nickel (II) complex undergoes changes in coordination, resulting in a series of color transitions. Initially, the solution is pale blue and then turns blue, followed by violet, and finally green. 
Final Answer: Option (3).