Question

Sc3+ is colourless but ti3+ is coloured why

Answer 1

Answer:

There is an electron free to jump between energy level. Thus Ti3+ ions selectively absorb certain colours, hence its solution is coloured. SC3+, on the other hand, has an empty d orbital; the [Sc(H2O)6]+3 complex has no electrons in T2g or eg orbitals. Hence SC3+ is colourless in aqueous solution.