The specific heats at constant pressure of some common gases are provided as a thirdorder polynomial: �;<<< = � + �� +
��C + ��E, with units J/(mol K). For methane (CH4) the coefficients are � = 19.89, � = 5.024 × 10NC, � = 1.269 × 10NO, � = −11.01 × 10NQ. At a production facility, the gas in a 50-liter tank is compressed to 3,600 psi (gage) during which time the temperature rises to 200°F. How much heat in J is given off as the gas cools to room temperature? Suppose the compressed gas is helium, how much heat would be given off in this case?