5. In the following take Cv = 20.8 and Cp = 29.1 J/mol-°C for nitrogen gas. (a) Three moles of nitrogen at 30 °C, contained in a rigid vessel, is heated to 250 °C. How much heat is required if the vessel has a negligible heat capacity? If the vessel weighs 100 kg and has a heat capacity of 0.5 kJ/kg-°C, how much heat is required? (b) Four moles of nitrogen at 200 °C is contained in a piston/cylinder arrangement. How much heat must be extracted from this system, which is kept at constant pressure, to cool it to 40 °C if the heat capacity of the piston and cylinder is neglected? %3D

5. In the following take Cv = 20.8 and Cp = 29.1 J/mol-°C for nitrogen gas. (a) Three moles of nitrogen at 30 °C, contained in a rigid vessel, is heated to 250 °C. How much heat is required if the vessel has a negligible heat capacity? If the vessel weighs 100 kg and has a heat capacity of 0.5 kJ/kg-°C, how much heat is required? (b) Four moles of nitrogen at 200 °C is contained in a piston/cylinder arrangement. How much heat must be extracted from this system, which is kept at constant pressure, to cool it to 40 °C if the heat capacity of the piston and cylinder is neglected? %3D

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 9.91PAE: 9.91 You want to heat the air in your house with natural gas (CH4). Assume your house has 275...

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