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प्रश्न
Comment on the statement that elements of the first transition series possess many properties different from those of heavier transition elements.
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उत्तर १
- In the first transition series, lower oxidation states are more stable, while heavier transition elements have higher oxidation states.
- The 5d transition series exhibits higher ionization enthalpy compared to the 3d and 4d transition series.
- M-M bonding is prevalent in heavier transition metals, but less so in the first series.
- The elements in the first transition series do not form complexes with coordination numbers of 7 or 8.
- Elements in the first series can form high or low-spin complexes based on ligand strength, while those in the other series form low-spin complexes regardless of ligand strength.
उत्तर २
This statement is true. According to the heavier transition elements (elements of the second and third transition series), the elements of the first transition series have different atomic radii, melting and boiling temperatures, ionization enthalpies, atomization enthalpies, and other characteristics. Their mentioned characteristics have significantly lower values.
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