chemistry question

Question

Calculate the standard enthalpy change for the reaction at 25^∘C. Standard enthalpy of formation values can be found in this list of thermodynamic properties.

C3H8(g)+5O2(g)⟶3CO2(g)+4H2O(g)

ΔH∘rxn = ____kJ

Answer 1

Sum of products - sum of reactants. Look up the values in the table of thermodynamic properties.

Be sure to multiply the tabular values by the coefficients in the equation. Thus, you'll have...

[3x∆H_CO2 + 4x∆H_H2O] - [∆H_C3H8 + 5xzero] = ∆Hrxn