Answer:
The heat of formation of SO2 is -296.1 kJ
Explanation:
<u>Step 1:</u> Data given
2S (s)+3O2 (g)→2SO3 (g) ΔH = -790.4 kJ
2SO2 (g)+O2 (g)→2SO3 (g) ΔH = -198.2 kJ
<u>Step 2</u>: Calculate the heat of formation of SO2
2 S(s) + 3 O2(g) --> 2 SO3(g) ΔH = -790.4 kJ
S(s) + 3/2 O2(g) → SO3(g) ΔH = -395.2 kJ
2SO2 (g)+O2 (g)→2SO3 (g) ΔH = -198.2 kJ
SO3(g) → SO2(g) + 1/2 O2(g) ΔH = 99.1 kJ
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S(s) + 3/2 O2(g) → SO3(g) ΔH = -395.2 kJ
SO3(g) → SO2(g) + 1/2 O2(g) ΔH = 99.1 kJ
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S (s)+O2 (g)→SO2 (g)
ΔHrxn = (-790.4 /2) kJ + (198.2/2) kJ
ΔHrxn = -395.2 kJ + 99.1 kJ = 296.1 kJ
The heat of formation of SO2 is -296.1 kJ
