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Question
The compounds of \[\ce{Ti^4+}\] ions are colourless due to ______.
Solution
The electronics configuration of
\[\ce{Ti = [Ar]}\]3d24s2 and
\[\ce{Ti^4+ = [Ar]}\]3d0
Due to the absence of unpaired electrons in 3d subshell, d-d transition is not possible. Therefore, \[\ce{Ti^4+}\] ions do not adsorb the radiation in the visible region. Hence, compounds of \[\ce{Ti^4+}\] ions are colourless.
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