In the following ions : Mn^(3+),V^(3+),Cr^(3+),Ti^(4+) (Atomic no. : Mn = 25, V = 23, Cr = 24, Ti = 22) (a) Which ion is most stable in an aqueous solution ? (b) Which ion is the strongest oxidising agent ? (c) Which ion is colourless ? (d) Which ion has the highest number of unpaired electrons ?

In the following ions : Mn^(3+),V^(3+),Cr^(3+),Ti^(4+) (Atomic no. :

1.	In the following ions : Mn^(3+),V^(3+),Cr^(3+),Ti^(4+) (Atomic no. : Mn = 25, V = 23, Cr = 24, Ti = 22) (a) Which ion is most stable in an aqueous solution ? (b) Which ion is the strongest oxidising agent ? (c) Which ion is colourless ? (d) Which ion has the highest number of unpaired electrons ?
Answer» Solution :`Mn^(3+),V^(3+),Cr^(3+),Ti^(4+)` (a) `Cr^(3+)` has the highest negative electrode potential, THEREFORE, it is most stable. (b) `Mn^(3+)` has `d^(4)` configuration, it has the maximum TENDENCY to gain one electron to change into stable HALF filled configuration, `d.^(5)`. Therefore it is the strongest oxidising AGENT. (c) `Ti^(4+)` has no electrons in the d-orbital, therefore no absorption of light and hence colourless. (d) `Mn^(3+)` has `d^(4)` configuration. The electrons occupy different orbitals. It has the highest number of unpaired electrons among the four.