CHE 3010 - Thermodynamics Venkat Padmanabhan Tennessee Tech University

CHE 3010 - Thermodynamics of Chemical ProcessesHomework 1 - Key

9/6/2017

1. Pressures up to 3000 bar are measured with a dead-weight gauge. The piston diameter is 4 mm. What is the approximate mass in kg of the weights required? Assume g = 9.8 m/s2. [Smith and van Ness Problem 1.5]

2. An instrument to measure the acceleration of gravity on Mars is constructed of a spring from which is suspended a mass of 0.4 kg. At a place on earth where the local g is 9.8 m/s2, the spring extends 1.08 cm. When the instrument package is landed on Mars, it radios the information that the spring is extended 0.4 cm. What is the Martian acceleration of gravity? Hint: The force on a spring is described by: F = Ksx where Ks is the spring constant and x is the length of extension. [Smith and van Ness Problem 1.11]

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CHE 3010 - Thermodynamics Venkat Padmanabhan Tennessee Tech University

3. A cylindrical vessel contains 7 g of nitrogen gas. How much work must be done to compress the gas at a constant temperature of 80oC until the volume is halved? [Assume nitrogen to be an ideal gas, R = 8.314 J/molK]

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CHE 3010 - Thermodynamics Venkat Padmanabhan Tennessee Tech University

4. 1 kg of liquid water at 100oC is converted to steam at 100oC by boiling at standard atmospheric pressure (1 atm). The volume of that water changes from an initial value of 1 L as a liquid to 1671 L as steam. [Assume that Lv of water = 2265 kJ/kg]

1. How much work is done by the system during this process? 2. How much energy is transferred as heat to the system? 3. What is the change in the system's internal energy during the process?

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CHE 3010 - Thermodynamics Venkat Padmanabhan Tennessee Tech University

5. How much heat is required to convert 200 g of ice at -20oC to steam at 100oC? [Assume the following: Lf of water = 334 kJ/kg, Lv of water = 2265 kJ/kg, cice = 2.09 kJ/kgK, cwater = 4.19 kJ/kgK]

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CHE 3010 - Thermodynamics Venkat Padmanabhan Tennessee Tech University

6. 5 kJ of heat is added to 2 moles of an ideal mono-atomic gas, initially at a temperature of 500 K, while the gas performs 7.5 kJ of work. What is the final temperature of the gas? [Assume: R = 8.314 J/molK]

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CHE 3010 - Thermodynamics Venkat Padmanabhan Tennessee Tech University

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