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Question
Account for the following :
Ti4+ is colourless whereas V4+ is coloured in an aqueous solutions.
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Solution
`"_22 Ti = [Ar]3d 4s^2`
22Ti4+ = [Ar]3d3 4S0 → No electrons for excitation so 4 Ti4+ is colourless.
23V = [Ar]3d3 4s2
V4+ = 3d1 4s0 → 1 electron is there for excitation and it impart blue colour in aquous
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