Anirudh Walia is teaching live on Unacademy Plus
(vii) Ionisation enthalpy It decreases from C to So. For Pb. it ie slightly higher than Sn. (vii) Electronegativity values The value decreases from C to Pb but not in a regular manner probably due to filling of d-orbitals III and Sn and f- orbitals In Pb. (ix) Catenation The greater the strength of element-element bond. the greater is the strength of catenation C> Si>Ge Sn> Pb (catenation). (x) Allotropy All the elements of this group except Pb exhibit allotropy. In cold countries white tin changes to grey tin and results in decrease in density. This is called tin disease or tin plague. (xi) Valency All elements exhibit tetra valency. In case of carbon, 406 kJ mol of energy is required for promotion of 2s - electron to 2p.
Formation of two extra bonds provide this energy. (xii) Atomic and ionic radii Both increase from C to Pb. (xii Multiple bonding Carbon forms pa pr bonds with itself and with S, N and O. Other clements show negligible tendency of this type due to their large size. Others form dr - pt multiple bonds.
Please share the videos as much as you can Each and every student has right to get the free education provided on this platform. God Bless U All Thanks for Watching