Question

Choose the complex which is paramagnetic
(i) $[Fe(H_{2}O{)}_6{]}^{2+}$ (ii) $K_3[Cr(CN{)}_6]$
(iii) $K_3[Fe(CN{)}_6]$ (iv) $K_2[Ni(CN{)}_4]$

• A. (i) , (ii) and (iii)
• B. (i), (iii) and (iv)
• C. (ii), (iii), and (iv)
• D. (i), (ii) and (iv)

Answer 1

Answer: (A)

(i) $[Fe(H_{2}O{)}_6{]}^{2+}$
(ii) $[Cr(CN{)}_6{]}^{3-}$
(iii) $[Fe(CN{)}_6{]}^{3-}$
(iv) $[Ni(CN{)}_4{]}^{2-}$
Thus complexes (i), (ii) and (iii) are paramagnetic species.