JEE Main20199 Jan 2019Morning ShiftChemistryCoordination CompoundsActual
Two complexes Cr H 2 O 6 Cl 3 A and Cr NH 3 6 Cl 3 B are violet and yellow coloured, respectively, The incorrect statement regarding them is:
Options
- ABoth are paramagnetic with three unpaired electrons
- BΔ 0 value of A is less than that of B
- CΔ 0 values of A and B are calculated from the energies violet and yellow light, respectively.
- DBoth absorb energies corresponding to their complementary colors.
Correct answer
C. Δ 0 values of A and B are calculated from the energies violet and yellow light, respectively.
Step-by-step solution
∆ 0 A < ∆ 0 B , both complex have C N = 6 , B has strong field ligand and A has weak field ligand so ∆ 0 A <   ∆ 0 B In both complexes, C r has 3 unpaired electrons and hence, will be paramagnetic C r H 2 O C l 3 Cr + 3 = 1 s 2    2 s 2    2 p 6   3 s 2   3 p 6    3 d 3 in strong field ligand or weak field ligand is t 2 g 1 , 1 , 1 , e g o Δ 0 order will be compared by spectrochemical series not by energies of violet and yello