The element that shows greater ability to form $p\pi - p\pi$ multiple bonds is

$(a)$ Classify the following oxides as neutral,acidic,basic,or amphoteric:
$CO, B_2O_3, SiO_2, CO_2, Al_2O_3, PbO_2, Tl_2O_3$
$(b)$ Write suitable chemical equations to show their nature.

Which of the following is $NOT$ a polymorphic form of silica $(SiO_2)$?

Consider the following reaction:
$R_2SiCl_2 + H_2O \to (1) \xrightarrow{\text{polymerisation}} (2)$
Compound $(2)$ in the above reaction is:

Which set of elements form electron precise hydrides?

$A$ thin film of aluminum deposited on glass acts as a good mirror because ...............