Heat of Combustion, Enthalpy, and Free Energy of Formation of Amino Acids and Related Compounds

Heat of combustion (Δ https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315314440/e2f9a2bb-7701-4891-988b-084507d1705c/content/ch5_equ_0001.tif"/> H c ° ) is given as the enthalpy change for the reaction of burning the compound at constant pressure to produce CO₂ (gas), H₂O (liquid), N₂ (gas), and S (rhombic). The enthalpy of formation (ΔHf°) is given for formation of the compound from C (graphite), H₂ (gas), O₂ (gas), N₂ (gas), and S (rhombic). In calculating ΔHf°, the enthalpies of formation of CO₂ (gas, p = 0) = 94.0518 Kcal mole^—1 and of H₂O (liquid) = 68.3174 Kcal mole^—1 were employed.¹ Most of the heats of combustion were originally reported as the enthalpy change for the combustion reaction with all gases at p = 1 atmosphere. No correction has been made for further expansion of the gases. However, all heats of combustion have been corrected so that International Atomic Weights of 1959 apply. The listings are for a temperature of 298.15°K. 0°C = 273.15°K and 1 cal = 4.1840 absolute joules. The units for all entries are kcal mole^—1.