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Question
Compare the chemistry of actinoids with that of the lanthanoids with special reference to oxidation state.
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Solution
Lanthanoids show limited oxidation states (+2, +3, +4), in which the +3 oxidation state is the most common. This is because of the large energy gap between the 4f, 5d, and 6s subshells. On the other hand, actinoids show a large number of oxidation states because the energy gap between 5f, 6d, and 7s subshells is smaller.
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