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9.96 Most first aid "cold packs" are based on the endothermic dissolution of ammonium nitrate in water:
A particular cold pack contains 50.0 g of NH4NO3 and 125.0 g of water. When the pack is squeezed, the NH4NO3dissolves in the water. If the pack and its contents are initially at 24.0°C, what is the lowest temperature that this bag could reach? (Assume that the ammonium nitrate solution has a specific heat of 4.25J g-l K-l, and that the heat capacity of the bag itself is small enough to be neglected.)
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Chapter 9 Solutions
Chemistry for Engineering Students
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