The pair in which both species have same magnetic moment (spin only value) is
[Cr(H2O)6]2+,[CoCl4]2+
[Cr(H2O)6]2+,[Fe(H2O)6]2+
[Mn(H2O)6]2+, [Cr(H2O)6]2+
[CoCl4]2-, [Fe(H2O)6]2+
The magnetic moment of K3[Fe(CN)6] is found to be 1.7 BM .How many unpaired electron (s) is/are present per molecule ?
1
2
3
4
An aqueous solution of CoCl2 on addition of excess of concentrated HCl turns blue due to formation of
[Co(H2O)4Cl2]
[Co(H2O)2Cl4]2-
[CoCl4]2-
[Co(H2O)2Cl2]
In which of the following pairs both the complexes show optical isomerism?
cis-[Cr(C2O4)2Cl2]3-, cis-[Co(NH3)4Cl2]
[Co(en)3]Cl3, cis-[Co(en)2Cl2]Cl
[PtCl(dien)]Cl, [NiCl2Br2]2-
[Co(NO3)3(NH3)3], cis-[Pt(en)2Cl2]
The correct order for the wavelength of absorption in the visible region is
[Ni(NO2)6]4- < [Ni(NH3)6]2+ < [Ni(H2O)6]2+
[Ni(NO2)6]4- < [Ni(H2O)6]2+ < [Ni(NH3)6]2+
[Ni(H2O)6]2+ < [Ni(NH3)6]2+ < [Ni(NO2)6]4-
[Ni(NH3)6]2+ < [Ni(H2O)6]2+ < [Ni(NO2)6]4-
A.
[Ni(NO2)6]4- < [Ni(NH3)6]2+ < [Ni(H2O)6]2+
The absorption of energy or the observation of colour in a complex transition compound depends on the charge of the metal ion and the nature of the ligands attached. The same metal ion with different ligands shows different absorption depending upon the type of ligand. The presence of weak field ligands make the central metal ion to absorb low energies i.e. of higher wavelength. The field strength of ligands can be obtained from spectrochemical series. i.e.
(weak field) I- < Br- < S2- < Cl- < NO3- < F- < OH- < H2O < NH3 < NO2- < CN- < CO (strong field)