Complete the Hess’ cycle using the values given in the table and hence calculate the enthalpy

change, ∆Hr
, for this reaction.
Show your working.
substance ∆Hf / kJmol–1
NO2(g) 34.0
H2O(l) –286
HNO3(l) –173
NO(g) 91.1
∆Hr
3NO2(g) + H2O(l) 2HNO3(l) + NO(g)

1 answer

dHrxn = (n*dHoproducts) - (n*dHoreactants)
Substitute the values and calculate. Show your work if you get stuck.