From the reactions, the metal complex formed is likely in the 4$^+$ oxidation state, which leads to no unpaired electrons. For such complexes, the spin-only magnetic moment is zero because all electrons are paired. Hence, the magnetic moment is:
\( \mu = 0 { BM}\)
Thus, the correct answer is (0).
Among the following cations, the number of cations which will give characteristic precipitate in their identification tests with
\(K_4\)[Fe(CN)\(_6\)] is : \[ {Cu}^{2+}, \, {Fe}^{3+}, \, {Ba}^{2+}, \, {Ca}^{2+}, \, {NH}_4^+, \, {Mg}^{2+}, \, {Zn}^{2+} \]