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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
How do the oxides of transition elements in lower oxidation states differ from those in higher oxidation state in the nature of metal-oxygen bonding and why?
✓

Answer

In the lower oxidation state the transition metal oxides are basic and they are acidic if the metal is in higher oxidation state. The oxides are amphoteric when the metal is in intermediate oxidation state. For example.
+3 +4 +7
$Mn_2O_3$ $MnO_2$ $Mn_2O_7$
Basic Amphoteric Acidic

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