Which of the following statements is correct for boric acid?

$Na_2B_4O_7 \cdot 10H_2O \xrightarrow{\text{Heat}} X + NaBO_2 + H_2O$,$X + Cr_2O_3 \xrightarrow{\text{Heat}} \underset{(\text{Green coloured})}{Y}$. $X$ and $Y$ are

Match the following compounds in List-$I$ with their uses in List-$II$:

List-$I$ (Compounds)	List-$II$ (Uses)
$A$. Boron-$10$	$I$. Antiseptic
$B$. Borax	$II$. Bullet proof vest
$C$. Boron-fibre	$III$. Neutron absorber
$D$. Orthoboric acid	$IV$. Heat resistance glasses

Give important trends and anomalous properties of boron.

$H_3BO_3$ or $B(OH)_3$ is considered as an acid because its molecule

Three pairs of compounds are given below. Identify the compound in each pair which has the group $13$ element in a more stable oxidation state. Give reasons for your choice and state the nature of bonding. $(A)$ $TlCl_3, TlCl$ $(B)$ $AlCl_3, AlCl$ $(C)$ $InCl_3, InCl$