A rigid vessel of volume 500.0 L contains carbon dioxide (CO2) initially at a pressure of...

 

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A rigid vessel of volume 500.0 L contains carbon dioxide (CO2) initially at a pressure of 300.0 kPa and a temperature of 300 K. Heat is added to the CO₂ by a 2.250 kW electric heater until the final temperature reaches 1200 K. During the heat addition process 155.0 kJ of energy is lost from the CO₂ to the environment. Assume the process can be approximated as an ideal gas. Determine the time (in seconds) the electric heater runs for assuming: i) Constant cold specific heats. ii) Constant average specific heats. iii) Variable specific heats using Table A-2c. iv) Variable specific heats using Table A-20 v) Comment briefly on the different accuracies of the results in parts i)-v). Using the result from part iv): vi) What is the final pressure? vii) Is the ideal gas assumption valid for an answer with less than 3% error? A rigid vessel of volume 500.0 L contains carbon dioxide (CO2) initially at a pressure of 300.0 kPa and a temperature of 300 K. Heat is added to the CO₂ by a 2.250 kW electric heater until the final temperature reaches 1200 K. During the heat addition process 155.0 kJ of energy is lost from the CO₂ to the environment. Assume the process can be approximated as an ideal gas. Determine the time (in seconds) the electric heater runs for assuming: i) Constant cold specific heats. ii) Constant average specific heats. iii) Variable specific heats using Table A-2c. iv) Variable specific heats using Table A-20 v) Comment briefly on the different accuracies of the results in parts i)-v). Using the result from part iv): vi) What is the final pressure? vii) Is the ideal gas assumption valid for an answer with less than 3% error?