Which of the following properties correctly explain $SiO_2$?

Which of the following elements reacts with water?

The correct statements with respect to halides of group $14$ elements are:
$I$. Both $CCl_4$ and $SiCl_4$ undergo hydrolysis
$II$. $GeX_4$ is more stable than $GeX_2$
$III$. $PbX_4$ is less stable than $PbX_2$
$IV$. Stability of dihalides decreases down the group.

Which element of group $14$ decomposes steam to form dioxide and dihydrogen gas?

Which of the following is not correct?

Which allotrope of carbon is isomorphous with crystalline silicon?