Answer:
Standard enthalpy of formation of Carbon disulfide CS2 = 87.3 KJ/mol
Explanation:
forming CS2 means that it should in the product side
C(graphite) + O2 → CO2 ΔH = -393.5
2S(rhombic) + 2O2 → 2SO2 ΔH = -296.4 x 2
CO2 + 2SO2 → CS2 + 3O2 ΔH = -1073.6 x -1
the second reaction is multiplied by 2 so that the SO2 and O2 can cancel out.
the third reaction is reversed (multiplied by -1) so that CS2 will be on the product side.
after adding the reaction and cancelling out similarities, the final reaction is: C(graphite) + 2S(rhombic) → CS2
Add ΔH to find the enthalpy of formation of CS2
ΔHf = (-393.5) + (-296.4 x 2) + (-1073.6 x -1) = 87.3 KJ/mol
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