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प्रश्न
Explain why:
(i) Mn2+ is more stable than Fe2+ towards oxidation to +3 state.
(At. no. of Mn = 25, Fe = 26)
(ii) Transition elements usually form coloured ions.
(iii) Zr and Hf exhibit similar properties.
(At. no. of Zr = 40, Hf = 72)
उत्तर
(i) This is because Mn2+(3d5) has an extra stable electronic configuration but Fe2+(3d6) does not.
(ii) This is due to the presence of impaired electrons in their (n-1) d – orbitals.
(iii) This is due to lanthanide contraction or ineffective shielding but intervening 4f- electrons in Hf.
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