Question

of 9. 10Dq is found to be 17400 cm-1 for [Cr(H20)6]3+. a) Predict #max in units of nm for the lowest energy d-d transition. b) Will this wavelength be longer, shorter, or the same if all of the water ligands are substituted with fluoride? Explain. [10]

Answer 1

Answer: 9. Given loDg that, is found to be 17400 cm for [Cr CH₂0/ 737 of her for the lowest (a) predict dmax in units Energy dad transition. Here, a loDq is the Energy difference between the lower Energy of a orbitals and higher Energy orbitals when splitting takes place an the transition metal orbitals. the geometry is octahedral, thus, trg orbital are lower energy orbitals and eg are higher energy orbitals. loDq = 17400 cmt. 000 So, the energy difference b/w two sets, ie, = 174oo cut long

we know Cmt is unit of wave numbes, ie, (2) thus = |ацоо сне (or) da 17400 cm 19H00 de 140 cm to 174 x 102 cm مہیا laux102 da 11 x 10 cm 2K d = 0.00575 x102410²m. d=575 8165 x 10 m d=5758 159 m d=575 um can cause Thus, the maximum wave length which transition from tog eg = 575 nm. (6) will this wavelength be longer, shorter, or the same if all of the water ligands are substituted with fluoride ? Explain.

Here , ligands a stronges then F and 0 H₂O is Thus the splitting will be smalled iff is ligands O Energy difference Llavelength will be is less and hence larges.