Question

$H _2 O _2$ can not be synthesized by

• A. Addition of ice cold $H _2 SO _4$ on $BaO _2$
• B. Addition of ice cold $H _2 SO _4$ and $PbO _2$
• C. Aerial oxidation of 2 ethyl anthraquinol
• D. Electrolysis of $\left( NH _4\right)_2 SO _4$ at a high current density

Answer 1

Answer: (B)

(i) $BaO _{2}( s )+ H _{2} SO _{4}( aq ) \rightarrow BaSO _{4}( s ) \downarrow+ H _{2} O _{2}$ (aq)
(ii) $PbO _{2}+2 H _{2} SO _{4} \rightarrow Pb \left( SO _{4}\right)+2 H _{2} O$
$PbO _{2}+2 H _{2} SO _{4} \stackrel{\Delta}{\rightarrow} 2 PbSO _{4}+ O _{2}+2 H _{2} O$
Aerial oxidation of 2-ethylanthraquinol produces 2-ethyl anthraquinone and hydrogen peroxide.
$\rightarrow$ Electrolysis of $\rightarrow\left( NH _{4}\right)_{2} SO _{4}$
(at cathode:- $H ^{+}$and $NH _{4}^{+}$ions attracted
$\rightarrow NH _{4}^{+} \rightarrow NH _{3( g )}+\stackrel{\oplus}{ H }$ (At Cathode : $2 H ^{+}+2 e ^{-} \rightarrow H _{2}$ )
At anode $OH ^{-}+ SO _{4}^{-2}$ ions get attracted
(Net oxidation: $4 OH ^{-} \rightarrow O _{2}+ H _{2} O _{2}+4 e ^{-}$)