Consider the following statements about group $13$ elements:
$A$. $AlCl_3$ achieves stability by forming a dimer.
$B$. $BCl_3$ is an electron-deficient molecule.
$C$. $E^0_{M^{3+}/M^0} \ (V)$ is $+1.26 \ V$ for aluminium.
$D$. In $+1$ oxidation state,thallium is unstable.
The incorrect statements are:

When borax is heated with $CoO$ on a platinum loop,the blue coloured bead formed is largely due to

Identify the correct statement for $B_2H_6$ from those given below.
$(A)$ In $B_2H_6$,all $B-H$ bonds are equivalent.
$(B)$ In $B_2H_6$ there are four $3$-centre-$2$-electron bonds.
$(C)$ $B_2H_6$ is a Lewis acid.
$(D)$ $B_2H_6$ can be synthesized from both $BF_3$ and $NaBH_4$.
$(E)$ $B_2H_6$ is a planar molecule.
Choose the most appropriate answer from the options given below.

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 $:$

Which of the following statements is incorrect?

Which of the following statements are not correct?
$i$. Atomic radius of $Ga$ is less than that of $Al$
$ii$. The order of ionization enthalpy of group $13$ elements is $B > Al > Ga > In > Tl$
$iii$. Boron trioxide is amphoteric in nature