Question:medium
Out of Fe$^{3+}$, Sc$^{3+}$, Cr$^{3+}$ and Co$^{3+}$ ions, the one which is colourless in aqueous solution is:
Out of Fe$^{3+}$, Sc$^{3+}$, Cr$^{3+}$ and Co$^{3+}$ ions, the one which is colourless in aqueous solution is:
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For transition metal ions, remember that the presence of unpaired electrons in the d-orbital often results in colored solutions.
Updated On: Feb 24, 2026
- Sc$^{3+}$
- Fe$^{3+}$
- Cr$^{3+}$
- Co$^{3+}$
Show Solution
The Correct Option is A
Solution and Explanation
The Sc$^{3+}$ ion, lacking unpaired electrons in its d-orbitals, does not absorb visible light and consequently appears colorless in aqueous solution. In contrast, other ions with unpaired electrons in their d-orbitals yield colored solutions.
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