Heat of Why Does Reaction Proceed Anyway?

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SUMMARY

The discussion centers on the dissolution of solid potassium chloride (KCl) in water, specifically addressing why the reaction proceeds despite the bonds formed having lower energy than those broken. The key conclusion is that the increased disorder from mixing leads to a rise in entropy, which drives the reaction forward. The correct answer to the posed question is (D), highlighting the significance of entropy in chemical reactions. This understanding clarifies the misconception that lower energy always correlates with exothermic reactions.

PREREQUISITES
  • Basic understanding of thermodynamics and chemical reactions
  • Familiarity with concepts of enthalpy and entropy
  • Knowledge of ionic compounds and their behavior in solvents
  • Understanding of exothermic and endothermic processes
NEXT STEPS
  • Study the principles of entropy and its role in chemical reactions
  • Learn about the thermodynamic properties of ionic compounds in solution
  • Explore the differences between exothermic and endothermic reactions
  • Investigate the concept of Gibbs free energy and its implications for reaction spontaneity
USEFUL FOR

Chemistry students, educators, and anyone interested in understanding the thermodynamic principles governing chemical reactions, particularly in the context of ionic compounds and dissolution processes.

brake4country
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Homework Statement


When solid potassium chloride is dissolved in water, the energies of the bonds formed are lower than the energies of the bonds broken. Why does the reaction proceed anyway?
(A) Undissolved potassium chloride compensates for the portion that dissolves
(B) The reaction does not take place under standard conditions
(C) The electronegativity of the water is increased by the interaction with potassium and chloride ions.
(D) The increased disorder due to the mixing results in an increased entropy of the system.

Homework Equations


na

The Attempt at a Solution


I solved this problem by process of elimination, but I must wonder: if the energies of the bonds formed are lower in energy, doesn't this imply that the products are more stable? Wouldn't it also imply that if this reaction were plotted as a bell-shaped curve, that it would resemble that of an exothermic reaction?
 
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"Stable?" Double and triple thinking things does not lead to increased understanding. Heat of fusion is it.
 
The reason I ask is because the solution states "if the bonds formed have lower energy than the bonds broken, the reaction is endothermic". I thought that lower energy would result in an exothermic process. What am I missing here?
 

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