$100 \ mL$ of $0.1 \ M$ $Fe^{2+}$ solution was titrated with $\frac{1}{60} \ M$ $Cr_2O_7^{2-}$ solution in acid medium. What is the volume (in $L$) of $Cr_2O_7^{2-}$ solution consumed?

Which of the following reactions is $NOT$ an example of a redox reaction?

$PbO$ and $PbO_2$ react with $HCl$ according to the following chemical equations:
$(i)$ $2PbO + 4HCl \to 2PbCl_2 + 2H_2O$
$(ii)$ $PbO_2 + 4HCl \to PbCl_2 + Cl_2 + 2H_2O$
Why do these compounds differ in their reactivity?

Match the chemical reactions given in List-$I$ with their types given in List-$II$:

List-$I$	List-$II$
$A$. $TiCl_{4(l)} + 2Mg_{(s)} \xrightarrow{\Delta} Ti_{(s)} + 2MgCl_{2(s)}$	$I$. Disproportionation reaction
$B$. $2H_2O_{2(aq)} \rightarrow 2H_2O_{(l)} + O_{2(g)}$	$II$. Metal displacement reaction
$C$. $C_{(s)} + O_{2(g)} \xrightarrow{\Delta} CO_{2(g)}$	$III$. Decomposition reaction
$D$. $2NaH_{(s)} \xrightarrow{\Delta} 2Na_{(s)} + H_{2(g)}$	$IV$. Combination reaction

Assign $A, B, C, D$ from the given type of reaction.
$Pb(NO_3)_2 + 2NaOH \longrightarrow Pb(OH)_2 \downarrow + 2NaNO_3$

Balance the following redox reactions using the oxidation number and ion-electron method:
$(1) \ Zn + NO_3^- + H^+ \to Zn^{2+} + N_2O + H_2O$
$(2) \ I^- + O_2 + H_2O \to I_2 + OH^-$
$(3) \ MnO_4^- + C_2H_5OH \to Mn^{2+} + CH_3COOH$