Assign reason for each of the following: (i) Manganese exhibits the highest oxidation state of+7 among the 3d series of transition elements. (ii)…

(i) Due to the participation of all 3d and 4s electrons in bond formation /due to the presence of maximum number of unpaired electrons.

(ii) Due to variable oxidation state / due to the ability to adopt multiple oxidation states / due to the large surface area / due to complex formation.

(iii) \(\displaystyle \mathrm{Cr}^{2+}\) changes from \(\displaystyle \mathrm{d}^{4}\) to stable half-filled \(\displaystyle \mathrm{t}_{2 \mathrm{~g}}{ }^{3}\) configuration while \(\displaystyle \mathrm{Mn}^{3+}\) changes to stable half-filled \(\displaystyle \mathrm{d}^{5}\) configuration.

(iv) Due to the absence of unpaired electrons and weak interatomic interactions.

(v) \(\displaystyle \mathrm{Cu}^{+}\)ion (aq.) undergoes disproportionation to \(\displaystyle \mathrm{Cu}^{2+}\) (aq.) and Cu / \[2 \mathrm{Cu}^{+} \text {(aq.) ⟶ } \mathrm{Cu}^{2+} \text { (aq.) + } \mathrm{Cu}(\mathrm{~s}) \]