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Question
What are alloys?
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Solution
An alloy is a blend of metals prepared by mixing the components. Alloys may be homogeneous solid solutions in which the atoms of one metal are distributed randomly among the atoms of the other.
RELATED QUESTIONS
Why is Sc3+ colourless while Ti3+ coloured? (Atomic number Sc = 21, Ti =22)
What are interstitial compounds?
Give reasons:
Transition metals show variable oxidation states.
Account for the following:
Zn is not considered as a transition element.
Which is a stronger reducing agent, Cr2+ or Fe2+ and why?
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.
The paramagnetic character in the 3d-transition series elements increases up to Mn and then decreases.
Electronic configuration of Mn2+ is ____________.
Which of the following will not act as oxidising agents?
(i) \[\ce{CrO3}\]
(ii) \[\ce{MoO3}\]
(iii) \[\ce{WO3}\]
(iv) \[\ce{CrO^{2-}4}\]
Which does not belong to first transition series?
Which of the following ions will exhibit colour in aqueous solution?
Account for the following:
Transition metals form alloys.
Which of the following ions acts as a typical transition metal ion?
Which property of transition metals enables them to behave as catalysts?
Complete the following reaction and justify that it is a disproportionation reaction:
\[\ce{3MnO^{2-}4 + 4H^+ -> \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{} + 2H2O}\]
Write the number of unpaired electrons in Cr3+.
(Atomic number of Cr = 24)
Explain the use of different transition metals as catalysts.
Account for the following:
Zirconium (Zr) and Hafnium (Hf) are difficult to separate.
Why are interstitial compounds well known for transition metals?
Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:
Atomic sizes
