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
Reactant B
Reactant C
Product A
Product B
Product C

Reactant A
Reactant B
Reactant C
Product A
Product B
Product C

Result(s):

Enthalpy Results (in kcal/mol)

Gibbs Free Energy Results (in kcal/mol)

Result

kcal/mol

Result

kcal/mol

Developed by

The Shodor Education Foundation, Inc.
in cooperation with the Department of Chemistry,
Appalachian State University