Gen Chem Problem..

[busdent]

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can you show me how to do this? thanks

Given ∆Hf for H2O(l) is –285.9 kJ/mol and ∆Hf for SO2(g) is –296.9 kJ/mol, calculate the enthalpy of formation, ∆Hf for H2S(g).
H2S(g) + 3/2O2(g) à H2O(l) + SO2(g) ∆H = - 562.6 kJ




A. + 20.2 kJ/mol
B. – 20.2 kJ/mol
C. + 1145.5 kJ/mol
D. – 1145.5 kJ/mol
E. 0 kJ/mol

The answer is B. thanks

 

[fancymylotus]

use the heats of formation and set it equal to the deltaH and make X the h2s concentration and solve,if i dont make sense,its cause its 3AM here.

 

[Euphoria36]

can you show me how to do this? thanks

Given ∆Hf for H2O(l) is –285.9 kJ/mol and ∆Hf for SO2(g) is –296.9 kJ/mol, calculate the enthalpy of formation, ∆Hf for H2S(g).
H2S(g) + 3/2O2(g) à H2O(l) + SO2(g) ∆H = - 562.6 kJ


A. + 20.2 kJ/mol
B. – 20.2 kJ/mol
C. + 1145.5 kJ/mol
D. – 1145.5 kJ/mol
E. 0 kJ/mol

The answer is B. thanks

i think its:

∆Hf = [∆ Hf of products] - [∆Hf of reactants]
= [∆Hf of H2O + ∆Hf SO2] - [∆Hf H2S]
= [-285.9 + -296.9] - [-562.6]
= -20.2