$CO_3^{2-}$ anion has which of the following characteristics?

The pair of molecules/ions with the same geometry but central atoms in different states of hybridization is:

The number of $S-S$,$S-O-S$,and $O-H$ linkages in a molecule of pyrosulphurous acid $(H_2S_2O_5)$ are respectively

What is chemical bonding? How is it formed,and what are its types?

Among the following,the correct statement$(s)$ is(are):
$A$. $Al(CH_3)_3$ has the three-centre two-electron $(3c-2e)$ bonds in its dimeric structure.
$B$. $BH_3$ has the three-centre two-electron $(3c-2e)$ bonds in its dimeric structure $(B_2H_6)$.
$C$. $AlCl_3$ has the three-centre two-electron bonds in its dimeric structure.
$D$. The Lewis acidity of $BCl_3$ is greater than that of $AlCl_3$.

Which of the following statements is correct?