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# Enthalpy and Gibbs Free Energy Calculator

Introduction : the purpose of this calculator is to calculate the value of the enthalphy of a reaction (delta H) or the Gibbs free energy of a reaction (delta G). The form below provides you with blanks to enter the individual enthalpies or free energy d ata points for a given reaction. Once entered, simply click on the "Evaluate" button to compute the appropriate value.

Note: if you do not have a second or third reactant or product, simply enter the value of "0" in the form.

The form below calculates the reaction enthalphy for:

NO3 + H2O -----> HNO3 + OH

Keep in mind the following rules:

Enthalphy Change Spontaneous Reaction?
Exothermic (dH < 0) Yes, dG < 0
Exothermic (dH < 0) If |T dS| < |dH|
Endothermic (dH > 0) If T dS > dH
Endothermic (dH > 0) No, dG > 0

### Input Value(s):

Enthalpy Results (in kcal/mol) Gibbs Free Energy Results (in kcal/mol)
 Reactant A None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HCl HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Reactant B None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HCl HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Reactant C None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HCl HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Product A None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HCl HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Product B None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HCl HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Product C None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HCl HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3
 Reactant A None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Reactant B None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Reactant C None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Product A None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Product B None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3 Product C None O(3P) O(1D) O(1S) O2(3sigma) O2(1delta) O2(1sigma) O3 H OH HO2 H2O H2O2 N N2 NO NO2 NO3 N2O4 N2O5 NH NH3 HNO HNO2 HNO3 S SO SO2 SO3 HS H2S CO CO2 CH3 CH4 HCO H2CO CH3O CH3O2 CH3OOH CH3NO2 CH3ONO CH3NO3 Cl ClO OClO ClO2 ClO3 HOCl NOCl ClNO2 ClNO3 Cl2O CF4 CClF3 CF2Cl2 CFCl3 CCl4 CH3Cl CH2Cl2 C2Cl4 CH3CCl3

### Result(s):

Enthalpy Results (in kcal/mol) Gibbs Free Energy Results (in kcal/mol)
 Result kcal/mol
 Result kcal/mol

Developed by
Shodor
in cooperation with the Department of Chemistry,
The University of North Carolina at Chapel Hill