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Efficient Net Energy Change

APCHEM-KLNXLI

Given the following information, which of the following reactions would be the MOST efficient in terms of energy usage for creating sulfuric acid for commercial use in regards to overall manufacturing costs?

Substance $\Delta H_f^\circ $ (kJ/mol)
$SO_{2(g)}$ -297
$SO_{3(g)}$ -396
$SO_2Cl_{2(g)}$ -364
$SO_{4(I)}$ -814
$H_2O_{(I)}$ -286
$HCl_{(g)}$ -92
A

Bubbling $SO_2Cl_2$ gas through water to create liquid dihydrogen sulfate and $HCl$ gas:

$SO_2Cl_2+ 2H_2O \longrightarrow H_2SO_4+ 2HCl$

B

Bubbling $SO_3$ gas through water to create liquid dihydrogen sulfate:

$SO_3+ H_2O \longrightarrow H_2SO_4$

C

Combining hydrogen gas and oxygen gas with sulfur vapor at extremely high temperatures to create liquid dihydrogen sulfate:

$H_2+ S+ O_2 \longrightarrow 2H_2SO_4$

D

Bubbling $SO_2$ gas through water to create liquid dihydrogen sulfate and hydrogen gas:

$SO_2+ 2H_2O \longrightarrow H_2SO_4+ H_2$