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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
Solution 1
Elements in the same horizontal group generally show the same number of oxidation states. The number of oxidation states shown by elements in the middle of each series is maximum, while those at the end are minimum.
Solution 2
Elements have varying oxidation states in both series. The highest oxidation state corresponds to the total amount of electrons in ‘s’ and ‘d’ orbitals. The 5d transition series shows fewer oxidation states than the 4d series. In 3d series, +2 and +3 oxidation states are common, resulting in stable complexes. In other series, OsO4 and PtF6 are stable at higher oxidation states.
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