Which is an amphoteric oxide?

The order of catenation property for $C, Si,$ and $Ge$ is $Ge < Si < C$. What will be the bond dissociation energy (in $kJ \ mol^{-1}$) for $C-C, Si-Si,$ and $Ge-Ge$ bonds respectively?

Which of the following is kept in water?

Identify the correct statements:
$I)$ $CO$ reduces the oxygen carrying ability of blood.
$II)$ Producer gas contains $CO$ and $N_2$.
$III)$ $C-O$ bond length in $CO_2$ is $115 \ pm$.

Among the given group $14$ elements,the one with highest density is

The catenation tendency of $C$,$Si$ and $Ge$ is in the order $Ge < Si < C$. The bond energies (in $kJ \ mol^{-1}$) of $C-C$,$Si-Si$ and $Ge-Ge$ bonds,respectively,are: