Question

The color of Iodine is
A) Violet
B) Green
C) White
D) Brown

Answer 1

Hint: We know that iodine is a chemical element with symbol “I” and atomic number 53. It belongs to group 17 and p-block.

Complete answer:

The Greek meaning of Iodine is purple or violet and this color is due to the colour of elemental iodine vapour. 

The Iodine is a bluish-black solid (at room temperature) with a metallic luster sublimating into violet-pink gas. And we know that this colour of iodine is because of the absorption of visible light by an electronic transition between highest and lowest molecular orbitals. 

In another way we can say the violet colour of iodine is due to the electronic transition of the lone pair to the antibonding sigma orbital which falls under visible light. For this transition Iodine absorbs red colour light from visible regions and emits violet colour.

So, the correct answer is “A”.

Additional information:

Iodine is purple in a hydrocarbon solvent and yellowish-brown in water. The colour of the Iodine solution depends upon the nature of the solvent. Iodide ions are colourless, for example a solution of sodium iodide is colourless, and this solution will only be coloured if the positive ions were to be coloured.

Note: We can also say it appears yellow in low concentration solution and brown in higher concentration solution. Under white light Iodine has a metallic appearance.