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The d & f Block Elements — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements3 Marks
Question
Give reasons for the following:
  1. Transition metals form alloys.
  2. $Mn_2O_3$ is basic whereas $Mn_2O_7$ is acidic.
  3. $Eu^{2+}$ is a strong reducing agent.
✓

Answer

  1. Due to comparable radii/ comparable size.
  2. In $Mn_2O_3$, Mn is in +3(lower) oxidation state while in $Mn_2O_7$​​​​​, Mn is in higher oxidation state (+7).
  3. Because its stable oxidation state is +3.

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