Question

You were asked previously to explain what you could deduce about the AH for the process of dissolving an unknown white solid into a beaker of water at 25 °C.

After the solid dissolved, the temperature of the solution decreased. Booster task: You find an answer online which states "The enthalpy of the dissolution process is negative(exothermic) because the temperature of the solution decreased." Explain WHY this answer is incorrect. Make sure you define what is the system, what are the surroundings, and talk about energy changes as it relates to bonds breaking/forming.

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