$BCl_3 + H_2O \longrightarrow$ Product,here product is:

Identify the correct statements about Boron.
$I.$ It has a high melting point.
$II.$ It has a high density.
$III.$ It has high electrical conductivity.
$IV.$ The $^{10}B$ isotope of it has a high ability to absorb neutrons.

Match List-$I$ with List-$II$:

List-$I$	List-$II$
$a$. Borax	$i$. $NaBO_2$
$b$. Kernite	$ii$. $Na_2B_4O_7 \cdot 4H_2O$
$c$. Orthoboric acid	$iii$. $H_3BO_3$
$d$. Borax bead	$iv$. $Na_2B_4O_7 \cdot 10H_2O$

Choose the correct answer from the options given below:

Which one of the following metallic oxides exhibits amphoteric nature?

The correct statements from the following are $:$
$(A)$ $Tl^{3+}$ is a powerful oxidising agent
$(B)$ $Al^{3+}$ does not get reduced easily
$(C)$ Both $Al^{3+}$ and $Tl^{3+}$ are very stable in solution
$(D)$ $Tl^{+}$ is more stable than $Tl^{3+}$
$(E)$ $Al^{3+}$ and $Tl^{+}$ are highly stable
Choose the correct answer from the options given below $:$

$Na_2B_4O_7$ $\xrightarrow{x} H_3BO_3$ $\xrightarrow{\Delta} B_2O_3$ $\xrightarrow{y} B$
Here $X$ and $Y$ are respectively: