Which of the following oxides is most acidic?

The electronegativity of a group $13$ element '$E$' is the same as that of $Ge$ (on the Pauling scale and up to one decimal point). The $CORRECT$ statements about $E^{3+}$ are:
$A$. It can act as a reducing agent.
$B$. It can act as an oxidizing agent.
$C$. $E^{3+}$ is more stable than $E^+$.
$D$. The standard electrode potential value for $E^{3+}/E$ is positive.

Which is used in the manufacture of safe matchsticks?

Nitrogen gas is liberated by thermal decomposition of

Which of the following oxides is the anhydride of orthophosphoric acid?

Describe the methods for the preparation of dinitrogen $(N_{2})$.