Which property of transition metals enables them to form alloys?
Show Hint
- High ionization enthalpy
- Similar atomic radii
- Catalytic property
- Complex formation
The Correct Option is B
Solution and Explanation
An alloy is a homogeneous mixture of two or more metals where atoms of one metal substitute atoms of another in the crystal lattice.
Step 2: Analysis
For such substitution to occur without distorting the metallic lattice significantly, the atomic radii of the metals involved must be comparable in size. Transition metals across the series have very similar atomic radii because the successive electrons are added to inner d-orbitals, providing effective nuclear shielding.
Step 3: Conclusion
Because transition metals have similar atomic radii, their atoms can replace each other in the crystal lattice, thereby forming stable alloys such as brass (Cu-Zn) and steel (Fe-C).
Final Answer: (B)
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Top CBSE CLASS XII General Properties of the Transition Elements (d-Block) Questions
- From the given data of standard electrode potential E°M2+/M values (in volts): Cr = -1.18, Mn = -1.18, Fe = -0.44, Co = -0.28, Ni = -0.25, Cu = +0.34, answer the following: (I) Why does E°M2+/M show an irregular trend in the above values? (II) Why is E°Cu2+/Cu value exceptionally positive? (III) Why is E°Mn2+/Mn value highly negative?
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- Why does Cr have a higher melting point than Mn?
- From the given data of E° values, answer the following questions:
E°M2+/M (V): Cr = –1.18, Mn = –1.18, Fe = –0.44, Co = –0.28, Ni = –0.25, Cu = +0.34
(I) Why does E°M2+/M show an irregular trend in the above values?
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