question_answer 57)

      Atomic number of Mn. Fe and Co are 25, 26 and 27 respectively. Which of the following inner orbital octahedral complex ions are diamagnetic? (a)            (b)    (c)     (        d)  

Answer:

                    (a, c) Molecular orbital electronic configuration of  in  is Number of unpaired electron = 0 Magnetic property = Diamagnetic Molecular orbital electronic configuration of in                 Number of unpaired electrons =2 Magnetic property = Paramagnetic Molecular orbital electronic configuration of  in  is Number of unpaired electron = 0 Magnetic property = Diamagnetic Molecular orbital electronic configuration of  in Number of unpaired electron = 1 Magnetic property = Paramagnetic Thus,  and  are diamagnetic. Hence, correct choices are options (a) and (c).