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Question
Which of the following lanthanoids show +2 oxidation state besides the characteristic oxidation state +3 of lanthanoids?
(i) \[\ce{Ce}\]
(ii) \[\ce{Eu}\]
(iii) \[\ce{Yb}\]
(iv) \[\ce{Ho}\]
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Solution
(ii) \[\ce{Eu}\]
(iii) \[\ce{Yb}\]
Explanation:
\[\ce{Ce}\] (Z = 57) = [Xe] 4f5 5d0 6s2, O.S. = + 3, + 4
\[\ce{Eu}\] (Z = 63) = [Xe] 4f7 5d0 6s2, O.S. = + 2, + 3
\[\ce{Yb}\] (Z = 70) = [Xe] 4f14 5d0 6s2, O.S. = + 2, + 3
\[\ce{Ho}\] (Z = 67) = [Xe] 4f11 5d0 6s2, O.S. = + 3
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