Calculate ΔH°rxn for 3NO2(g)+1H2O(l) → 2HNO3(g)+1NO(g)

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SUMMARY

The discussion focuses on calculating the standard enthalpy change (ΔH°rxn) for the reaction 3NO2(g) + 1H2O(l) → 2HNO3(g) + 1NO(g). The enthalpies of formation provided are NO2 (g): 33.10 kJ/mol, H2O (l): -285.83 kJ/mol, HNO3 (l): -174.10 kJ/mol, and NO (g): 90.29 kJ/mol. To accurately compute ΔH°rxn, it is essential to account for the phase change of HNO3 from liquid to gas by incorporating the latent heat of vaporization (Hvap) for HNO3, as the enthalpy of formation for HNO3 is given for its liquid state.

PREREQUISITES
  • Understanding of enthalpy of formation
  • Knowledge of phase changes and latent heat
  • Familiarity with thermodynamic equations, specifically dHrxn = dHproducts - dHreactants
  • Basic principles of chemical reactions and stoichiometry
NEXT STEPS
  • Research the latent heat of vaporization (Hvap) for HNO3
  • Learn how to apply Hess's Law in thermodynamic calculations
  • Study the concept of standard enthalpy change in chemical reactions
  • Explore the enthalpy of formation for various states of matter
USEFUL FOR

Chemistry students, educators, and professionals involved in thermodynamics and reaction energetics will benefit from this discussion.

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Homework Statement



Using the enthalpies of formation given below, calculate ΔH°rxn in kJ, for the following reaction.

3NO2(g)+1H2O(l) -> 2HNO3(g)+1NO(g)

NO2 (g): 33.10 kJ/mol
H2O (l): -285.83 kJ/mol
HNO3 (l): -174.10 kJ/mol
NO (g): 90.29 kJ/mol

Homework Equations



dHrxn = dHproducts - dHreactants

The Attempt at a Solution



Is this possible to do since the equation says HNO3 is a gas, but they give the enthalpy of formation for HNO3 as a liquid.
 
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its possible but you need to use another enthalpy term that accounts for the latent heat which is from the phase transfer of liquid to gas
 
That would be the Hvap of HNO3.
 

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