$B_4C$ (boron carbide) is used except:

$H_3BO_3 + H_2O_2 \to H_2O + 'X' \xrightarrow{NaOH} 'Y'$
Which of the following statements is/are correct for $'Y'$?

The number of terminal and bridging hydrogens in $B_2H_6$ are respectively

What is the nature of $Al_2O_3$?

In the following reaction,assign the nature of the product formed by the complete hydrolysis of the underlined atom at $R.T.$:
$H_4\underline{P}_2O_5 + H_2O \longrightarrow \text{Products}$

When an aqueous solution of borax is acidified with hydrochloric acid,a white crystalline solid is formed which is soapy to touch. Is this solid acidic or basic in nature? Explain.