The purple colour of iodine vapours is due to:a)d–d transitionb)...
Due to the electronic transition of n (lone pair) to sigma* (antibonding sigma orbital) which fall under Visible light hence iodine shows violet color.
For that mentioned transition iodine absorb red color light from visible region and emit violet color hence appear as violet.
Lone pair of e absorb energy and shift to sigma antibonding orbital and shows color.
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The purple colour of iodine vapours is due to:a)d–d transitionb)...
Explanation:
When iodine crystals are heated, they sublimate and turn into a purple vapour. The purple colour of iodine vapours is due to the * * transition.
* * Transition:
* * transition involves an electronic transition between two d orbitals of the same metal ion. It occurs when a metal ion with a partially filled d orbital absorbs light and an electron is promoted to a higher energy level within the d orbital.
In case of iodine vapours:
Iodine atoms in the vapour phase exist as I2 molecules, which have a symmetric covalent bond between the two iodine atoms. The electrons in the covalent bond form a bonding molecular orbital and an antibonding molecular orbital. When iodine molecules are heated, they absorb energy and the electrons in the antibonding molecular orbital are excited to a higher energy level. This results in the formation of a temporary excited state of the molecule. When this excited state molecule returns to its ground state, it releases the excess energy as a photon of light with a wavelength of around 500 nm, which corresponds to the purple colour.
Conclusion:
Thus, the purple colour of iodine vapours is due to the * * transition, which involves the excitation of electrons between two d orbitals of the same metal ion.
The purple colour of iodine vapours is due to:a)d–d transitionb)...
This is based upon homo & lumo concept