Aqueous solutions of $Na_2S_2O_3$ on reaction with $Cl_2$ gives

Assign $A, B, C, D$ from the given type of reaction.
$3PbS + 8HNO_3 \text{ (dil.)} \longrightarrow 3Pb(NO_3)_2 + 3S \downarrow + 2NO + 4H_2O$

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

$PbS + 4O_3 \,\to ?\,+\,4O_2$

How many moles of $K_2Cr_2O_7$ will be reduced by $1$ mole of $Sn^{2+}$ ions?

Only $2 \ mL$ of $KMnO_4$ solution of unknown molarity is required to reach the end point of a titration of $20 \ mL$ of oxalic acid $(2 \ M)$ in acidic medium. The molarity of $KMnO_4$ solution is: (in $M$)