1. What is the difference between the heat of reaction, Qrxn,and the enthalpy of reaction, ï„Hrxn? (
2. In a coffee-cup calorimeter, 1.40 g of NH4NO3 is mixed with71.0 g of water at an initial temperature of 25.00 oC. Afterdissolution of the salt, the final temperature of the calorimetercontent is 23.39 oC. Assuming the solution has a heat capacity (Cp)of 4.18 J/ oC•g and assuming no heat loss to the calorimeter(surroundings), calculate the enthalpy change for the dissolutionof NH4NO3 in units of kJ/mol. (MW(NH4NO3) = 80.05 g/mol)
3. How do cold packs and hot packs work? What kind ofthermodynamic process is involved in a hot pack?
4. Who uses hot packs and cold packs? What kind of process isinvolved in a cold pack?
5. What is the chemical that is used in hot packs that use asuper cooled fluid? Why is that chemical a good choice for use tomanufacture a hot pack?
