What is ΔHof of Al2S3(s)?
2Al2S3(s) + 9O2(g) → 2Al2O3(s) + 6SO2(g) ΔHo = -3684.2 kJ
ΔHof Al2O3(s) = -1675.7 kJ/mol
ΔHof SO2(g) = -296.8 kJ/mol
-724.0 kJ
-5656.7 kJ
-5132.2
-1711.7 kJ
The calculation of ΔHof of Al2S3(s) can be done by using the enthalpy change of the balanced chemical equation given and the given enthalpies of formation of Al2O3(s) and SO2(g).
First, let's determine the moles of Al2O3(s) and SO2(g) formed in the reaction:
2 moles of Al2O3 are formed for every 2 moles of Al2S3 reacted.
6 moles of SO2 are formed for every 2 moles of Al2S3 reacted.
Next, let's calculate the enthalpy change for the formation of Al2S3(s):
ΔHof Al2S3(s) = (2 * ΔHof Al2O3(s)) + (6 * ΔHof SO2(g)) - (2 * ΔHo)
ΔHof Al2S3(s) = (2 * -1675.7 kJ/mol) + (6 * -296.8 kJ/mol) - (2 * -3684.2 kJ)
ΔHof Al2S3(s) = -3351.4 kJ/mol - 1780.8 kJ/mol + 7368.4 kJ
ΔHof Al2S3(s) = 2236.2 kJ/mol
Therefore, the ΔHof of Al2S3(s) is 2236.2 kJ/mol. However, none of the given answer options match this result.