How to Calculate the Enthalpy of Formation of HCl?

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SUMMARY

The discussion focuses on calculating the enthalpy of formation of gaseous hydrogen chloride (HCl) at 298.15 K using thermodynamic data. Key values provided include the enthalpy changes for reactions involving ammonia (NH3), ammonium chloride (NH4Cl), and their respective solvation energies. The formula for calculating enthalpy, ΔH = Σ H(products) - Σ H(reactants), is emphasized as essential for solving the problem. Participants suggest reviewing Hess's law and clarify the need for the correct formation equation for HCl.

PREREQUISITES
  • Understanding of thermodynamic principles, specifically enthalpy of formation
  • Familiarity with Hess's law and its application in thermochemical calculations
  • Knowledge of standard enthalpy values for chemical species involved
  • Basic skills in manipulating chemical equations and stoichiometry
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  • Review Hess's law and its applications in calculating enthalpy changes
  • Learn how to use standard enthalpy of formation values for various compounds
  • Investigate the concept of solvation energy and its relevance in thermodynamic calculations
  • Explore examples of calculating enthalpy changes for different chemical reactions
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Chemistry students, educators, and anyone studying thermodynamics, particularly those focusing on enthalpy calculations and reaction energetics.

Lindsayyyy
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Hi

Homework Statement


I shall calculate the enthalpy of formation of gaseous hydrogen chlorid at 298,15 K
with the usage of thw following data:

\Delta [NH_{3}+HCL -&gt;NH_{4}] :-50,4 kJmol^{-1}<br /> \Delta H_{form} NH_{3}:-46,2kJmol^{-1}<br /> NHCL_{4}:-315kJmol^{-1}

and <br /> \Delta H_{solv} NH_{3}:-35,7kJmol^{-1}<br /> HCL:-73,5kJmol^{-1}<br /> NH_{4}CL:+16,4kJmol^{-1}

Homework Equations



I know that I need the formula that

\Delta H=\Sigma H(products) - \Sigma H(educts)



The Attempt at a Solution



Well to be honest I don't know where to start, our notes are just useless from the professor and I don't find anything useful on the internet. Would be nice if anyone could give me some hints.

Thanks for the help
 
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the second list are all of those energies of solvation? What level of chemistry is this? You may need to look at Hess's law for this problem but usually you don't use energy of solvation in these...

Do you have an equation for the formation that you want to use..are they looking for HCl coming from hydrogen and chlorine only or from something else.
 

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