Problem: Calculate the standard entropy change for the reaction 2H2(g)+O2(g)→2H2O(l) using the data from the following table:SubstanceΔH°f (kJ/mol)ΔG°f (kJ/mol)S° [J/(K•mol)]H2O(g)0.000.00130.6O2(g)0.000.00205.0H2O(l)-285.8-237.269.90

FREE Expert Solution

We can use the following equation to solve for ΔS˚rxn:

S°rxn = S°prod-S°react 

Note that we need to multiply each S˚ by the stoichiometric coefficient since S˚ is in J/mol • K. 


The given reaction is 2H2(g)+O2(g)→2H2O(l)


Given: 

S° H2O(g) = 130.6 J/(K•mol)

S° O2(g) = 205.0 J/(K•mol)

S° H2O(l) = 69.90 J/(K•mol)


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Problem Details

Calculate the standard entropy change for the reaction 2H2(g)+O2(g)→2H2O(l) using the data from the following table:

SubstanceΔH°f (kJ/mol)ΔG°f (kJ/mol)S° [J/(K•mol)]
H2O(g)0.000.00130.6
O2(g)0.000.00205.0
H2O(l)-285.8-237.269.90

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