(a) Following are the transition metal ions of 3d series:
`Ti^(4+),V^(2+),Mn^(3+),Cr^(3+)`
(Atomic numbers: `Ti=22,V=23,Mn=25,Cr=24`)
Answer the following:
(i) Which ion is most stable in an aqueous solution and why?
(ii) Which ion is a strong oxidising agent and why?
(iii) Which ion is colourless and why?
(b) Complete the following equations:
(i) `2MnO_(4)^(-)+16H^(+)+5S^(-)to`
(ii) `KMnO_(4)overset(heat)to`

Explanation

(i) `Cr^(3+)` because of half filled `t_(2g)^3` configuration.
(ii)` Mn^(3+)` due to stable do configuration of `Mn^(2+)` .
(iii)` Ti^(4+)` because it has no unpaired electrons.