COMEDK2024Morning ShiftChemistryd and f Block ElementsActual
Match the compounds given in Column I with their characteristic features listed in Column II No. Column I No. Column II A La(OH)₃ P Acidic in nature B Mn₂O₇ Q Least basic C Lu(OH)₃ R Interstitial compound D Fe₃H S Most basic
Options
- Aarray llll A = Q & B = P & C = S & D = R array
- BA = S B = P C = Q D = R
- CA = S B = R C = Q D = P
- Darray llll A = R & B = P & C = S & D = Q array
Correct answer
B. A = S B = P C = Q D = R
Step-by-step solution
The basicity of lanthanoid hydroxides Ln ( OH )₃ decreases as the ionic radius of the lanthanoid ion Ln ³⁺ decreases due to lanthanoid contraction. La ³⁺ has the largest ionic radius, making La ( OH )₃ the most basic, while Lu ³⁺ has the smallest ionic radius, making Lu ( OH )₃ the least basic. Thus, A = S and C = Q . Mn ₂ O ₇ is an oxide of manganese in a high oxidation state ( +7 ), which makes it acidic in nature. Thus, B = P . Fe ₃ H is a non-stoichiometric hydride of iron, which is classified as an interstitia