Assign $A, B, C, D$ from the given type of reaction.
$Na_2CO_3 + PbSO_4 \longrightarrow PbCO_3 \downarrow + Na_2SO_4$

How many moles of $KMnO_4$ are required to oxidize $1 \ mol$ of $Fe(C_2O_4)$ in an acidic medium?

For the reaction:
$I^{-} + ClO_{3}^{-} + H_{2}SO_{4} \longrightarrow Cl^{-} + HSO_{4}^{-} + I_{2}$
The correct statement$(s)$ in the balanced equation is/are:
$A$. Stoichiometric coefficient of $HSO_{4}^{-}$ is $6$.
$B$. Iodide is oxidized.
$C$. Sulphur is reduced.
$D$. $H_{2}O$ is one of the products.

$C +$ Conc. $H_2SO_4 \xrightarrow{\Delta} X + Y + H_2O$. $X$ and $Y$ in the above reaction are:

Which of the following is a redox reaction?

Justify that the reaction:
$2 Cu_{2}O_{(s)} + Cu_{2}S_{(s)} \rightarrow 6 Cu_{(s)} + SO_{2(g)}$
is a redox reaction. Identify the species oxidised/reduced,which acts as an oxidant and which acts as a reductant.