The name 'silica' covers an entire group of minerals which have the general formula `SiO_2` , most common of which is quartz. quartz is a frame work silicate with the `SiO_4` tetrahedra arratnged in spirals . The spirals can turn in a clockwise or anti-clockwise direction - a feature that results in these being two mirror images optically active, varieties of quartz.
The following pictures represent various silicate anions.
Their formulae are respectively : ` (##KSV_INORG_CHM_P1_C07_E01_035_Q01.png" width="80%"> .

Options

A. `SiO_(3)^(2-)` `Si_(3)O_(7)^(2-)`
B. `SiO_(4)^(4-)` `Si_(3) O_(10)^(8-)`
C. `SiO_(4)^(2-)` `Si_(3)O_(9)^(2-)`
D. `SiO_(3)^(4-) Si_(3)O_(7)^(8-)`

Answer

B