Answer:The statement which is false is d
Explanation:
The color which we see from our eyes is basically the complementary color of wavelength of light which is absorbed.
The wavelegth of light follows the following sequence:
Violet<Indigo<Blue<Green<Yellow<Orange<Red.
So the shortest wavelegth is of violet light and longest wavelength of light is Red.
Since energy is E=hv=hc/λ ;So energy is inversely related with wavelegth and hence
For ligand X the complex has blue color and so we can ascertain that ligand X would have absorbed the Red light as the complementary color of blue light is Red.So the complex of ligand X absorbs the longest wavelegth and hence the energy gap between the two split d-orbitals t2g and eg would be very less. Larger the energy gap between t2g and eg orbitals more stronger is the ligand .
So X would be a weak field ligand.
For ligand Y the complex has yellow color and so we can ascertain that ligand Y would have absorbed the Violet light as the complementary color of yellow light is violet. Violet has the lowest wavelegth and hence the energy gap between the two split d-orbitals t2g and eg would be very large. Larger the energy gap between t2g and eg orbitals more stronger is the ligand .
So Y is a strong field ligand.
For ligand Z the complex has red color and so we can ascertain that ligand Z would have absorbed the blue light as the complementary color of red light is blue.The wavelegth of blue light lies between violet and red hence the energy gap between the two split d-orbitals t2g and eg would be in between than the other two liagnds.
So Z would be moderate field ligand.
options A , B and C are correct statements.
option D is incorrect because Z absorbs the moderate wavelegth.
The answer is d as it is only statement which is incorrect.
J. Hope this helps you!