Which of the following is oxidised by $SO_2$?

When $CuSO_4$ reacts with $KI$,the oxidation number of $Cu$ changes by

Consider the following reactions (unbalanced):
$Zn +$ hot conc. $H_2SO_4 \rightarrow G + R + X$
$Zn +$ conc. $NaOH \rightarrow T + Q$
$G + H_2S + NH_4OH \rightarrow Z$ (a precipitate) $+ X + Y$
Choose the correct option$(s)$.
$(1)$ The oxidation state of $Zn$ in $T$ is $+1$
$(2)$ Bond order of $Q$ is $1$ in its ground state
$(3)$ $Z$ is dirty white in colour
$(4)$ $R$ is a $V$-shaped molecule

Chlorine oxidises sulphur dioxide in the presence of water to give an oxyacid $A$. Chlorine also oxidises iodine in the presence of water to give an oxyacid $B$. The oxidation states of $S$ and $I$ in $A$ and $B$ are respectively

Identify the redox reactions among the following and determine the oxidizing and reducing agents in them:
$(a) 3HCl_{(aq)} + HNO_{3_{(aq)}} \to Cl_{2_{(g)}} + NOCl_{(g)} + 2H_2O_{(l)}$
$(b) HgCl_{2_{(aq)}} + 2KI_{(aq)} \to HgI_{2_{(s)}} + 2KCl_{(aq)}$
$(c) Fe_2O_{3_{(s)}} + 3CO_{(g)} \xrightarrow{\Delta} 2Fe_{(s)} + 3CO_{2_{(g)}}$

In the following reaction,$\text{SO}_2 + 2\text{H}_2\text{S} \to 3\text{S} + 2\text{H}_2\text{O}$,which choice has a value twice that of the equivalent mass of the oxidising agent?