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Questions
Account for the following:
Sc3+ is colourless whereas Ti3+ is coloured in an aqueous solution.
Account for the following:
Ti3+ is coloured whereas Sc3+ is colourless in an aqueous solution.
Solution
Sc3+: [Ar]18
Ti3+: [Ar]18 3d1
Ti3+ is coloured in an aqueous solution due to the presence of one unpaired electron, whereas Sc3+ is colourless.
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