A calorimeter contains 510 mL of water at 21.5oC. A 323 g piece of iron is heated in a Bunsen burner flame, then quickly submerged in the water in the calorimeter. After adding the hot iron, the temperature of the water in the calorimeter rises to a maximum of 37.7oC. Determine the temperature (in oC) to which the piece of iron was heated. Use the following values for your calculations. specific heat of water: 4.184 J/goC density of water: 1.0 g/mL specific heat of iron: 0.449 J/goC oC

9.97 Suppose that the working fluid inside an industrial refrigerator absorbs 680 J of energy for every gram of material that vaporizes in the evaporator. The refrigerator unit uses this energy flow as part of a cyclic system to keep foods cold. A new pallet of fruit with a mass of 500 kg is placed in the refrigerator. Assume that the specific heat of the fruit is the same as that of pure water because the fruit is mostly water. Describe how you would determine the mass of the working fluid that would have to be evaporated to lower the temperature of the fruit by 15C. List any information you would have to measure or look up.

Hydrogen is an ideal fuel in many respects; for example, the product of its combustion, water, is nonpolluting. The heat given off in burning hydrogen to gaseous water is 5.16 104 Btu per pound. What is this heat energy in joules per gram? (1 Btu = 252 cal; see also Table 1.4.)

Swimming Pool A swimming pool measuring 20.0m12.5m is filled with water to a depth of 3.75m. If the initial temperature is 18.4°C, how much heatmust be added to the water to raise its temperature to29.0°C? Assume that the density of water is 1.000 g/mL.