Which of the following is expected to be a paramagnetic complex?

Options

A. `[Ni(H_(2)O)_(6)]^(2+)`
B. `[NI(CO)_(4)]`
C. `[Zn(NH_(3))_(4)]^(2+)`
D. `[Co(NH_(3))_(6)]^(3+)`

Answer

A

Explanation

In the complex the outer electronic configuration of Ni(II) is `d^(8)` . It has two unpaired electrons which cannot pair up in the presence of `H_(2)O` molecules which are weak ligands . The complex is paramagnetic in nature.