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प्रश्न
Name a member of the lanthanoid series that is well-known to exhibit +2 oxidation state.
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उत्तर
Europium (Eu) is well-known to exhibit +2 oxidation state due to its half filled f orbital in +2 oxidation state.
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संबंधित प्रश्न
Complete the following equation :
`2MnO_4^(-)+6H^++5NO_2^(-)rarr`
Complete the following equations : 2 Na2CrO4 + 2 H + →
Answer the following question.
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(a) \[\ce{Cu^{+} -> Cu^{2+} + Cu}\]
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(c) \[\ce{2KMnO4 -> K2MnO4 + MnO2 + O2}\]
(d) \[\ce{2MnO^{-}4 + 3Mn^{2+} + 2H2O -> 5MnO2 + 4H^{+}}\]
Generally transition elements and their salts are coloured due to the presence of unpaired electrons in metal ions. Which of the following compounds are coloured?
(i) \[\ce{KMnO4}\]
(ii) \[\ce{Ce(SO4)2}\]
(iii) \[\ce{TiCl}\]
(iv) \[\ce{Cu2 Cl2}\]
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Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
