Sir i didnot understand the decreasing order of extent of overlapping given below... will you please explain this...

Priyanshu kumar Best Answer

When the principal quantum number n is less, then overlapping is stronger. The extent of overlap is higher for s orbital than for p orbital. Higher is the extent of overlap, stronger is the bond formed. As we know, the atoms combine by colliding with each other, In this process, two atoms come very close to each other and they penetrate each other's orbital and form a new hybridized orbital. The bonding pair of electrons reside in this new hybridized orbital. This orbital has lower energy than the atomic orbital and hence it is stable. This entire process is known as orbital overlap. :- The extent of overlap depends on several parameters. In general, we can say that, the stronger is the bond formed between the two atoms, greater the overlap. The bond strength mainly depends upon two factors. :-They are the effectiveness of overlapping (Angular concentration) and extent of overlapping (size of lobe). Bond strength is directly proportional to the percentage s character. As the s character increases, bond strength of orbitals will also increase. Thus, s-s orbital overlapping will have a higher bond strength. s-s overlap is the mutual overlap between two half filled s orbitals of two atoms. The spherical shape of s orbital and overlapping taking place in all directions to some extent makes the newly formed s-s bond non-directional. -Another important thing that matters in the bond strength by overlapping orbitals is the principal quantum number. In a 1s orbital 1 is the principal quantum number. As the principal quantum number increases the extent of overlapping would decrease. Considering these factors and rules for determining extent of overlapping given in your study material,you can determine this order easily.