Problem: Standard thermodynamic quantities for selected substances at 25 °C SubstanceΔHf ( kJ/mol)Na(s)0.0Na(g)107.5Cl(g)121.3Cl2(g)0.0NaCl(s)-411.2Pb(s)0.0Pb(g)195.2Pb(NO3)2(s)-451.9N(g)472.7N2(g)0.0O(g)249.2O2(g)0.0O3(g)142.7What is the value of ΔH for this reaction? (Formation of Pb(NO3)2(s))

FREE Expert Solution

We are asked what is the value of ΔH for this reaction? (Formation of Pb(NO3)2(s))

Balanced reaction: 

Pb(s) + N2(g) + 3 O2(g) → Pb(NO3)2(s)


Since this is a formation equation, the ΔH°f of the product is already the ΔH°rxn.

This is because the ΔH°f of reactants are all zero. 


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Problem Details

Standard thermodynamic quantities for selected substances at 25 °C 

SubstanceΔHf ( kJ/mol)
Na(s)0.0
Na(g)107.5
Cl(g)121.3
Cl2(g)0.0
NaCl(s)-411.2
Pb(s)0.0
Pb(g)195.2
Pb(NO3)2(s)-451.9
N(g)472.7
N2(g)0.0
O(g)249.2
O2(g)0.0
O3(g)142.7



What is the value of ΔH for this reaction? (Formation of Pb(NO3)2(s))

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