Discussion Forum

 The unbalanced chemical reactions give in list I show missing reagent or condition (?)  which are provided in list II. Match List I with List II  and select the correct answer using the code given below the lists 

Answer:

Explanation:

(P)   $2PbO_{2}+2H_{2}SO_{4}$    $\underrightarrow{warm(3)}$         $2PbSO_{4}+O_{2}+2H_{2}O$

(Q)    $Na_{2}S_{2}O_{3}+H_{2}O$     $\underrightarrow{Cl_{2}(4)}$ $NaHSO_{4}+HCl$

 (R)      $N_{2}H_{4}$   $\underrightarrow{I_{2}(2)}$  $N_{2}+HI$

(S)     $XeF_{2}$        $\underrightarrow{NO(1)}$  Xe+NOF

 Thus , P - (3) , Q - (4), R- (2), S -(1)