$Kieselghur$ is an amorphous form of silica which is used in filtration plants. Which of the following is true about it?

What is aluminosilicate? Which ions are used to balance its electric charge?

It is observed that $Pb^{2+}$ is more stable than $Pb^{4+}$, while $Sn^{2+}$ is less stable than $Sn^{4+}$. Consider the following reactions:
$PbO_{2} + Pb \rightarrow 2PbO; \Delta_{r}G^{\circ} (1)$
$SnO_{2} + Sn \rightarrow 2SnO; \Delta_{r}G^{\circ} (2)$
Identify the correct set from the following.

Consider the following route of reactions $R_2SiCl_2 + H_2O \to (A) \xrightarrow{\text{Polymerisation}} (B)$. Compound $(B)$ in the above reaction is:

Consider the oxides of group $14$ elements $SiO_2$,$GeO_2$,$SnO_2$,$PbO_2$,$CO$ and $GeO$. The amphoteric oxides are

Which of the following is true for diamond?