Question

The dissociation pressure of
`CaCO_(3)(s) overset(Delta) rarr CaO(s) +CO_(2)` gets doubled over a tempertaure range of `60` degree around the mean tempertaure of `837^(@)C`. Calculate the enthalpy of dissociation in kcal `mol^(-1)`.

Answer 1

`((T_(1)+T_(2)))/(2) = 837^(@)C`
`T_(1) -T_(2) = 60^(@)C`
`T_(1)T_(2) = 1140 xx1030`
Solve `T_(1) = 867^(@)C = 1140 K`
`T_(2) = 807^(@)C = 1080 K`
`"log"(K_(2))/(K_(1)) = "log"(P_(2))/(P_(1)) = (DeltaH)/(2.303R) [(60)/(1140 xx1080)]`
`log2 = (DeltaH)/(2.303 xx 2xx 10^(-3)) xx (60)/(1140 xx 1080)`
`DeltaH = 28.44 kcal mol^(-1)`