2) A cold pack consists of an inner pouch containing ammonium nitrate,NH4 NO3 (s), and an outer pouch of water. Twisting the pack breaksthe inner pouch and allows the water and ammonium nitrate to mix. Asthe ammonium nitrate dissolves, the temperature of the surroundingsdecreases. The energy change per mole of ammonium nitrate disso-ciated is 25-7 kJ.a) Classify the reaction as endothermic or exothermic.b) Draw a potential energy diagram for the reaction. Label the change inenthalpy.c) Write a thermochemical equation for this reaction.

a) The given reaction is endothermic. This is because it is clearly given to the question that when…

Answered: 2) A cold pack consists of an inner…

Chemistry for Engineering Students

4th Edition

ISBN:9781337398909

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter9: Energy And Chemistry

Section: Chapter Questions

Problem 9.101PAE

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9.96 Most first aid "cold packs" are based on the endothermic dissolution of ammonium nitrate in water: NH4NO3(s)NH4+(aq)+NO3(aq) H= 25.69 kJ 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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