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प्रश्न
The compounds of \[\ce{Ti^4+}\] ions are colourless due to ______.
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उत्तर
The electronics configuration of
\[\ce{Ti = [Ar]}\]3d24s2 and
\[\ce{Ti^4+ = [Ar]}\]3d0
Due to the absence of unpaired electrons in 3d subshell, d-d transition is not possible. Therefore, \[\ce{Ti^4+}\] ions do not adsorb the radiation in the visible region. Hence, compounds of \[\ce{Ti^4+}\] ions are colourless.
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संबंधित प्रश्न
Why do interstitial compounds have higher melting points than corresponding pure metals?
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Sc3+, V3+, Ti4+, Mn2+ (At. Nos. Sc = 21, V = 23, Ti = 22, Mn = 25)
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Cu+2 salts are coloured, while Zn2+ salts are white.
The elements of 3d transition series are given as: Sc Ti V Cr Mn Fe Co
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Cu+ ion is unstable in aqueous solution.
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3d3
For M2+/M and M3+/M2+ systems, the E° values for some metals are as follows:
| Cr2+/Cr | −0.9 V |
| Mn2+/Mn | −1.2 V |
| Fe2+/Fe | −0.4 V |
| Cr3/Cr2+ | −0.4 V |
| Mn3+/Mn2+ | +1.5 V |
| Fe3+/Fe2+ | +0.8 V |
Use this data to comment upon:
- The stability of Fe3+ in acid solution as compared to that of Cr3+ or Mn3+ and
- the ease with which iron can be oxidised as compared to a similar process for either chromium or manganese metal.
How would you account for the following:
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(A) Duralumin
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(C) Spiegeleisen
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