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प्रश्न
Why do interstitial compounds have higher melting points than corresponding pure metals?
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उत्तर
The melting points of interstitial compounds are higher than those of pure metals because of bonding between the metal and the non-metal, which is stronger than metal–metal bonding.
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संबंधित प्रश्न
Why is Sc3+ colourless while Ti3+ coloured? (Atomic number Sc = 21, Ti =22)
Which metal in the first transition series (3d series) exhibits + 1 oxidation state most frequently and why?
How would you account for the following?
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Cu+ ion is unstable in aqueous solution.
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How would you account for the following:
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Cu2+
Indicate how would you expect the five 3d orbitals to be occupied for this hydrated ions (octahedral).
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Following are the transition metal ions of 3d series:
Ti4+, V2+, Mn3+, Cr3+
(Atomic numbers: Ti = 22, V = 23, Mn = 25, Cr = 24)
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1) Which ion is most stable in an aqueous solution and why?
2) Which ion is a strong oxidising agent and why?
3) Which ion is colourless and why?
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Why do transition metals exhibit higher enthalpy of atomization?
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Although \[\ce{Cr^3+}\] and \[\ce{Co^2+}\] ions have same number of unpaired electrons but the magnetic moment of \[\ce{Cr^3+}\] is 3.87 B.M. and that of \[\ce{Co^2+}\] is 4.87 B.M. Why?
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\[\ce{MO3F}\]
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On the basis of the figure given below, answer the following questions:
- Why Manganese has lower melting point than Chromium?
- Why do transition metals of 3d series have lower melting points as compared to 4d series?
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| 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:
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Oxidation states
