Question

1. A gas does 800 J of work to expand and push a piston. If the total energy of the gas does not change, what is the heat for this process? Take the bold work to be the system.

2. Sodium dimer (Na₂) has a vibrational constant of 159.13 cm^-1. Calculate the vibrational partition function of Na₂ to three significant figures at 300 K. The degeneracy is 1.

3. Calculate the work done (in J) when the volume of an ideal gas changes from 1.00 L to 3.00 L at an initial temperature of 25 degrees celsius and at a constant pressure of 1 bar.

Answer 1

• A gas does 800 J of work to expand and push a piston. If the total energy of the gas does not change, what is the heat for this process? Take the bold work to be the system.

  and

  

  

  

  

• Sodium dimer (Na2) has a vibrational constant of 159.13 cm-1. Calculate the vibrational partition function of Na2 to three significant figures at 300 K. The degeneracy is 1.

  

  

  

• Calculate the work done (in J) when the volume of an ideal gas changes from 1.00 L to 3.00 L at an initial temperature of 25 degrees celsius and at a constant pressure of 1 bar.

Values:

P= 1bar (100,000 Pa)

Vi= 1.00 L (0.001 m³)

Vf= 3:00 L (0.003 m³)