In the reaction $B_2O_3 + C + Cl_2 \to A + CO$,the $A$ is:

Which of the following is an amphoteric oxide?

Boric acid is polymeric due to

Explain the following:
$(1)$ Aluminum forms $[AlF_6]^{3-}$ ion but boron does not form $[BF_6]^{3-}$ ion.
$(2)$ $PbX_2$ is more stable than $PbX_4$.

Basicity of $H_3BO_3$ is :

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 $:$