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Question
Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:
Oxidation states
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Solution
The first series of transition metals (3d series) stable forms lower oxidation states like +2 and +3, and its highest states are strongly oxidizing. Conversely, down the respective vertical columns, the second (4d) and third (5d) series show an increasing stability in their higher oxidation states (such as +6 and +8), making their lower oxidation states relatively uncommon and unstable.
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