for the same monodent ligand which metal ion can form more stable complex a)Mn2+ b)Fe2+ c)co2+ d)Ni2+
Hey!
The stability of the complex depends on the size of the metal ion. The smaller the size of the metal ion, the more stable with the metal complexes.
The stability order of the complexes mentioned in the question is: mn2+< fe2+< Co2+< Ni2+
Hope this answer helps!