Exam 19: The First Law of Thermodynamics

A cylinder contains 24.0 moles of an ideal gas at a temperature of 300 K.The gas is compressed at constant pressure until the final volume equals 0.63 times the initial volume.The molar heat capacity at constant volume of the gas is and the ideal gas constant is .The change in the internal (thermal)energy of the gas is closest to

The figure shows a pV diagram for 0.95 mol of gas that undergoes the process 1 → 2.The gas then undergoes an isochoric heating from point 2 until the pressure is restored to the value it had at point 1.What is the final temperature of the gas? The ideal gas constant is R = 8.314 J/mol • K = .

The process shown in the pV diagram in the figure is

When an ideal gas increases in volume at constant pressure,the average kinetic energy of the gas molecules

The figure (not to scale)shows a pV diagram for 1.8 g of helium gas (He)that undergoes the process .Find the value of V₃.The ideal gas constant is R = 8.314 J/mol • K = 0.0821 L • atm/mol • K,and the atomic weight of helium is 4.0 g/mol.

An ideal gas is allowed to expand slowly at constant temperature to twice its original volume.During the expansion,the gas absorbs 200 kJ of heat. (a)What is the change in the internal (thermal)energy of the gas during the expansion? (b)How much work does the gas do during the expansion?

A container with rigid walls is filled with 4 mol of air with C_V = 2.5R.How much does the internal (thermal)energy change if the temperature of the air rises from 16°C to 437°C? The ideal gas constant is .

When a gas undergoes an isothermal process,there is

The figure shows the pV diagram for a certain thermodynamic process.In this process, of heat flows into a system,and at the same time the system expands against a constant external pressure of If the volume of the system increases from to calculate the change in internal (thermal)energy of the system.If the internal (thermal)energy change is nonzero,be sure to indicate whether this energy change is positive or negative.

The figure shows a pV diagram for 0.0066 mol of gas that undergoes the process 1 → 2 → 3.What is the pressure p₂.The ideal gas constant is R = 8.314 J/mol • K = .

A certain amount of ideal monatomic gas is maintained at constant volume as it is cooled from 455K to 405 K.This feat is accomplished by removing 400 J of heat from the gas.How much work is done by the gas during this process? The ideal gas constant is R = 8.314 J/mol • K.

An adiabatic compression is performed on an ideal gas.The final pressure is equal to 0.560 times the initial pressure and the final volume equals 1.50 times the initial volume.What is the adiabatic constant for the gas?

The process shown in the T-V diagram in the figure is an

An ideal gas is compressed in a well-insulated chamber using a well-insulated piston.This process is

The temperature of an ideal gas in a sealed 0.40 container is reduced from 400 K to The final pressure of the gas is The molar heat capacity at constant volume of the gas is 28.0 J/mol • K.The work done by the gas is closest to

In an isochoric process,the internal (thermal)energy of an ideal gas decreases by 50 J.How much work does the gas do during this process?

The figure shows a pV diagram for 8.3 g of nitrogen gas (N₂)in a sealed container.The temperature T₁ of the gas in state 1 is 79°C.What are (a)the pressure p₁ of the gas in state 1 and (b)the temperature T₂ of the gas in state 2? The ideal gas constant is R = 8.314 J/mol • K = ,and the ATOMIC weight of nitrogen is 14 g/mol.

The pV diagram shown is for 7.50 moles of an ideal diatomic gas taken through a cycle from a to b to c.The ideal gas constant is R = 8.314 J/mol • K. (a)What is the highest temperature reached by the gas during the cycle? (b)What net work does the gas do during the cycle? (c)How much heat is exchanged with the gas during part bc of the cycle? Does it enter or leave the gas? (d)What is the change in the internal (thermal)energy of the gas during part bc of the cycle? (e)What is the change in the internal (thermal)energy of the gas during the entire cycle?

An expansion process on an ideal diatomic gas has a linear path between the initial and final states on a pV diagram.The initial pressure is the initial volume is and the initial temperature is The ideal gas constant is .The final pressure is and the final temperature is The work done by the gas is closest to

The process shown in the pV diagram in the figure is an