Dissolution of LiCl•3H2O in LiCl solution

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gfd43tg
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A liquid solution of LiCl in water at 25 C contains 1 mole of LiCl and 7 moles of water. If 1 mole of LiCl•3H2O is dissolved isothermally in this solution, what is the heat effect?


Here is my attempt with a relevant table and graph, but I wonder if my net equation represents the situation and if my intermediate reactions are okay. I just made the intermediates arranged to get the final equation the way I wanted. I can't really say how every intermediate reaction is representing the physical situation

Here is my attempt
 
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  • Handwritten Hess's law cycle for dissolving LiCl•3H2O in LiCl solution, with equations and enthalpy values, a boxed final result of ΔH = 43,231 J, and side notes on ΔH°f and heat of solution.
    9.4 attempt 1.jpg
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  • Printed textbook page 444 listing heats of formation of LiCl solids and heats of solution of LiCl in 3, 5, 8, 10, 12 and 15 mol H2O, in joules.
    9.4 data.jpg
    47.1 KB · Views: 969
  • Graph of enthalpy of solution ΔH, kJ per mol of solute, against n̄ in moles of H2O per mole of solute on a logarithmic axis from 1 to 800, with curves labelled HCl(aq) and LiCl(aq).
    9.4 graph.jpg
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edited to put all photos on one post. I wish the phone app could flip the photos around instead of having to go onto my laptop
 
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I don't think you have to care about whole Hess cycle. Why don't you read heat of dissolution (from the plot) for both solutions as if they were prepared from water and anhydrous LiCl, and just subtract one from another?