question_answer 53)

  Catenation, i.e., linking of similar atoms depends on size and electronic configuration of atoms. The tendency of catenation in group 14 elements follows the order : (a) \[C\text{ }>\text{ }Si>\text{ }Ge\text{ }>\text{ }Sn\]                                                                (b) \[C\text{ }>\text{ }Si\text{ }>\text{ }Ge\text{ }\approx \text{ }Sn\] (c) \[Si\text{ }>\text{ }C\text{ }>\text{ }Sn\text{ }>\text{ }Ge\]                                 (d)  \[Ge\text{ }>\text{ }Sn\text{ }>\text{ }Si\text{ }>\text{ }C\]

Answer:

  (b) The decrease in catenation property is linked with M-M bond energy which decreases from carbon to tin. \[C-C\]                                  \[Si-Si\]     83 kcal/mol                         54 kcal/mol \[GeGe~~~~\]                  \[SnSn\] 40 kcal/mol                         37 kcal/mol Thus, two options (a) and (b) are correct in this question but option (b) is more appropriate. \[C>>Si\]                                             >             \[Ge\approx Sn\] Large difference in energy                           Small difference in energy