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How would you account for the following:...

How would you account for the following: i. Of the `dot d^(4)` species, `Cr ^2+` is strongly reducing while manganese(III) is strongly oxidising. ii. Cobalt(II) is stable in aqueous solution but. in the presence of complexing reagents it is easily oxidised. ii. The d^1 configuration is very unstable in ions?

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1. .(Cr)^(2+ is reducing as it involves change trom ) (d)^(4). to ). .(d)^(3)., the latter is rorestable configuration .(Mn)(III). to .(Mn)(I). is from .3 (~d)^(+). to .3 (~d)^(s)., again .3 (~d)^(s). is,anra stable configuration. ii. Due to CFSE, which more than compensates the 3rd IE. iii. The hydration or lattice energy more. penates the ionisation enthalpy involved in re moving electron fronted
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V PUBLICATION-THE d- AND f- BLOCK ELEMENTS-QUESTION BANK
  1. Compare the stability of +2 oxidation state for the elements of the fi...

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  2. Compare the chemistry of actinoids with that of the lantlanoids with s...

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  3. How would you account for the following: i. Of the dot d^(4) species, ...

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  4. What is meant by "disproportionation'? Give two examples of disproport...

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  5. Which metal in the first series of transition metals exhibits +1 oxida...

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  6. Calculate the number of unpaired electrons in the following gaseous io...

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  7. Give example and suggest reasons for the following features of the tra...

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  8. Describe the method of preparation of potassium dichromate from chromi...

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  9. What are alloys? Name an important alloy which contains some of the la...

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  10. What are inner transition elements? Decide which of the following atom...

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  11. The chemistry of the actinoid elements is not so smooth as that of the...

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  12. Which is the last element in the series of the actinoids? Write the el...

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  13. Use Hund's' rule to derive the electronic configuration of '(Ce)^(3+)'...

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  14. Name the members. of the lanthanide series which exhibit +4 oxidation ...

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  15. Compare the chemistry of actinoids with that of the lantlanoids with s...

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  16. Write the electronic configuration of the element with the atomic numb...

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  17. Compare the general characteristics of the first series of the transit...

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  18. Write down the number of 3 d electrons in each of the following ions: ...

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  19. Comment on the statement that elements of the First transition series ...

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  20. What can be inferred from the magnetic. Moment values of the following...

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