Anhydrous $AlCl_3$ is obtained from

Identify the compounds $A$,$X$ and $Z$ in the following reactions :
$A + 2HCl + 5H_2O \to 2NaCl + X$
$X$ $\xrightarrow[370 \ K]{\Delta} HBO_2$ $\xrightarrow[> 370 \ K]{\Delta} Z$

Choose the incorrect statement/reaction.

Diborane reacts with ammonia to form $X$, which on heating gives $H_2$ and borazine. $X$ is

Which of the following substances is formed when $BCl_3$ reacts with water?

Which of the following is the correct match?