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The d & f Block Elements — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements1 Mark
MCQ
Most copper (I) compounds are found to be colourless. This is due to:
  • A
    Presence of low oxidation state of copper.
  • B
    Completely filled d-level in Cu(I).
  • C
    Diamagnetic nature of the compound.
  • D
    High polarizability of Cu(I) ion.
✓

Answer

  1. Completely filled d-level in Cu(I).

Explanation:

In copper (I) ion there are no vacant d orbitals as it is diamagnetic. Copper(I) ion being less charged has small ligand field effect and the transition is in the infrared region in which no color is perceived by human eye.

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