Same chapter3 marksDifficulty: Medium
Why do transition metals and their compounds act as good catalysts?
d- and f-Block Elements
3 marksDifficulty: Medium
Why are most transition metal compounds coloured?
Original Khojo Papers practice question — not from a past board paper.
Answer
In a complex the five d orbitals are split into two sets of slightly different energy. An electron can absorb light of the right frequency and be promoted from the lower set to the higher, and the colour seen is the complement of the light absorbed. An ion with an empty or a completely filled d subshell has no such transition available and is colourless.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Zn2+ and Sc3+ compounds are colourless for exactly this reason.
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