Question

Which of the followings are not a general formula of silicate ion present cyclic silicates ?

• A. $Si{O}_4^{4-}$
• B. $S{i}_2{O}_5^{2-}$
• C. $S{i}_2{O}_7^{6-}$
• D. $(Si{O}_3{)}_n^{2n-}$

Answer 1

Answer: (A), (B), (C)

$S{i}_2{O}_7^{6-}$

Cyclic silicates contain $(Si{O}_3{)}_n^{2n^{-}}$ or $(Si{O}_3^{2-}{)}_n$ ions which are formed by linking three or more tetrahedral $Si{O}_4^{4-}$ units cyclically. Each unit shares two oxygen atoms with other units.
Hence a, b, c are not general formula of cycic silicates.