iran-konkur 2016 Q219

iran-konkur · Other · konkur-riazi_1395_specialized Not Maths
219- Considering the reaction: $Pb(\text{s}) + PbO_2(\text{s}) + 2H_2SO_4(\text{aq}) \rightarrow 2PbSO_4(\text{s}) + 2H_2O(\text{l})$, if 35 grams of lead is consumed in this reaction, how many kilojoules of energy are released? ($Pb \approx 207\ \text{g.mol}^{-1}$)
Compound$H_2SO_4(\text{aq})$$PbO_2(\text{s})$$H_2O(\text{l})$$PbSO_4(\text{s})$
$\Delta H_f$ (kJ)$-814$$-277$$-286$$-918$

(1) $1385$(2) $1505$(3) $1881$(4) $2515$

\textbf{219-} Considering the reaction: $Pb(\text{s}) + PbO_2(\text{s}) + 2H_2SO_4(\text{aq}) \rightarrow 2PbSO_4(\text{s}) + 2H_2O(\text{l})$, if 35 grams of lead is consumed in this reaction, how many kilojoules of energy are released? ($Pb \approx 207\ \text{g.mol}^{-1}$)

\begin{center}
\begin{tabular}{|c|c|c|c|c|}
\hline
Compound & $H_2SO_4(\text{aq})$ & $PbO_2(\text{s})$ & $H_2O(\text{l})$ & $PbSO_4(\text{s})$ \\
\hline
$\Delta H_f$ (kJ) & $-814$ & $-277$ & $-286$ & $-918$ \\
\hline
\end{tabular}
\end{center}

\begin{tabular}{llll}
(1) $1385$ & (2) $1505$ & (3) $1881$ & (4) $2515$
\end{tabular}

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