Silicon. The element silicon has two allotropic modification (a) Amorphous silicon (b) Adamantine silicon. A third allotropic modification has been observed and is of doubtful character known as graphitoidal silicon. Amorphous silicon is obtained by heating well-powdered quartz of finely silica with magnesium powder in a fireclay which is suitable for the manufacute of crucibles. `SiO_(2)+2Mg to Si+2MgO` The product is washed with dilute HCl to wash away MgO and then with hydrofluoric acid to remove uncharged silica. When silica is heated with carbon then silica is reduced toA. SiB. SiOC. `SiO_(3)^(2-)`D. SiC

Silicon. The element silicon has two allotropic modification (a) Amorp

1.	Silicon. The element silicon has two allotropic modification (a) Amorphous silicon (b) Adamantine silicon. A third allotropic modification has been observed and is of doubtful character known as graphitoidal silicon. Amorphous silicon is obtained by heating well-powdered quartz of finely silica with magnesium powder in a fireclay which is suitable for the manufacute of crucibles. `SiO_(2)+2Mg to Si+2MgO` The product is washed with dilute HCl to wash away MgO and then with hydrofluoric acid to remove uncharged silica. When silica is heated with carbon then silica is reduced toA. SiB. SiOC. `SiO_(3)^(2-)`D. SiC
Answer» Correct Answer - D

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