Paramagnetism in transition metal ions results from the presence of unpaired electrons, each carrying a magnetic moment associated with spin and orbital angular momentum. In compounds of the first series, the contribution of orbital angular momentum is effectively quenched.

Diamagnetic substances are repelled, while paramagnetic substances are attracted by an applied magnetic field. Ferromagnetism, an extreme form of paramagnetism, is characterized by very strong attraction to the magnetic field.

The unexpected E⁰ values for Mn, Ni, and Zn are linked to their electronic configurations. The stability of half-filled d subshell (d⁵) in Mn²⁺ and completely filled d subshell (d¹⁰) in Zn is related to their E⁰ values, while for ...

The decreasing tendency in E⁰ values for M²⁺/M reflects a trend towards less negative values across the transition metal series, which is associated with the increase in the sum of the first and second ionization enthalpies.

Noble transition metals are unaffected by single acids due to their low reactivity. In contrast, most first-series metals, excluding copper, are more reactive and undergo oxidation by 1M H⁺, albeit sometimes at a slow rate.