See image — AITS & Test Series Chemistry Question

💡 Solution & Explanation

Cyclic silicate having three Si atoms   6 3 9 Si O  contains three Si – O – Si linkage. One tetrahedron shares three oxygen atoms while other share two oxygen atoms and these two tetrahedrons constitute one unit. Therefore, number of oxygen atoms sheared per tetrahedron or Si atom = 3 2 1 2 2 2    General formula of double chain silicates :   6n 4 11 n Si O .  As the tendency of formation of multiple bond increases the extent of polymerization decreases. Silicon has large size hence, it forms less effective p p overlapping with oxygen.