Chemistry - Complete d-block Question with Solution | TestHub
In the following reactions, the underlined metal may or may not undergo a change in its magnetic nature (i.e., paramagnetic → diamagnetic or diamagnetic → paramagnetic). Determine the number of reaction in which such a change occurs. (i) (ii) (iii) (iv) (v) (vi) (vii)
Answer:
Solution:
Based on the electronic configurations of the transition metal elements before and after the reactions:
Reaction (ii): Changes from paramagnetic Mn²⁺ () to diamagnetic MnO₄⁻ ().
Reaction (iii): Changes from paramagnetic Cr³⁺ () to diamagnetic Cr₂O₇²⁻ ().
Reaction (iv): Changes from diamagnetic (NH₄)₂Cr₂O₇ () to paramagnetic Cr₂O₃ ().
Reaction (vii): Involves another change in oxidation state and coordination structure that alters the magnetic property.
Thus, the total number of reactions that undergo a change in magnetic nature is 4.
