Which one of the following is an outer orbital complex and exhibits paramagnetic behaviour?
[Ni(NH3)6]2+
[Zn(NH3)6]2+
[Cr(NH3)6]3+
[Co(NH3)6]3+
As we discussed in the concept
is a border line ligand which can work as weak field as well as strong field ligand. With , work as weak field ligand that's why it is unable to pair the unpaired electrons of which results outer orbital complex with paramagnetic character.
Option 1)
[Ni(NH3)6]2+
Correct
Option 2)
[Zn(NH3)6]2+
Incorrect
Option 3)
[Cr(NH3)6]3+
Incorrect
Option 4)
[Co(NH3)6]3+
Incorrect