Which of the following non-metal elements has half the atomicity of sulfur?

How many corners of $SiO_4$ units are shared in the formation of three dimensional silicates?

Discuss the preparation and properties of silicones.

Identify the correct statements from the following.
$(i)$ Quartz is a piezoelectric material.
$(ii)$ All group $14$ tetrachlorides except $CCl_4$ are easily hydrolyzed in water.
$(iii)$ The $C-C$ bond distance within the layer of graphite is $154 \ pm$.
$(iv)$ $SiO_2$ is soluble in aqueous $HCl$ solution.

Non-oxide ceramics can be

The catenation tendency of $C$,$Si$ and $Ge$ is in the order $Ge < Si < C$. The bond energies (in $kJ \ mol^{-1}$) of $C-C$,$Si-Si$ and $Ge-Ge$ bonds,respectively,are: