12. Provide the thermochemical equation for ∆Hf° for solid copper(II) oxide. (5 pts)

13. If 156 g of water at 22 °C is mixed with 85.2 g water at 95 °C, what is the final temperature of the water? The specific heat of water is 4.184 J/g•°C. (6 pts)

14. When 5.44 g NH4NO3(s) is added to 150.0 g water in a coffee-cup calorimeter, the temperature decreases from 18.6 °C to 16.2 °C. The solution has a specific heat capacity of 4.2 J/g•°C. Calculate ∆H for the process. (6 pts)