Question

Which of the following arrangements represent the correct order of the property stated against it ?
(i) `Ni^(2+) lt Co^(2+) lt Fe^(2+) lt Mn^(2+)` : ionic size
(ii) `Co^(3+) lt Fe^(3+) lt Cr^(3+) lt Sc^(3+)` : stability in aqueious solution
(iii) `Sc lt Ti lt Cr lt Mn` : number of oxidation states
(iv) `V^(2+) lt Cr^(2+) lt Mn^(2+) lt Fe^(2+)` : paramagnetic behaviour
A. Sc gt Ti gt Cr lt Mn : number of oxidation states
B. `V^(2+) ltCr^(2+) ltMn^(2+) ltFe^(2+)` : paramagnetic behaviour
C. `Ni^(2+) lt Co^(2+) ltFe^(2+) ltMn^(2+)` : ionic size
D. `Co^(3+) lt Fe^(3+) lt Cr^(3+) lt Sc^(3+)` : stability in aqueous solution.

Answer 1

Correct Answer - B
Number of unpaired electrons in `Fe^(2+)` is less than `Mn^(2+)`, so `Fe^(2+)` is less paramagnetic than `Mn^(2+)`.