32 What temperature rise is produced when 0.45 kJ is transferred to the internal energy of 0.50 mole of an ideal gas at constant volume?
33 Explain the differences between the concepts of internal energy, thermal energy and temperature.
34 When a fixed mass of a particular gas expands by a certain amount, compare the amount of work that would be done in isobaric, adiabatic and isothermal changes. Explain your answer.
35 When 100 J of thermal energy was transferred to a gas it expanded and did 30 J of work. What was the change in internal energy?
36 Explain why a gas gets hotter when it is compressed rapidly.
37 When a gas expanded isothermally, 3000 J of work were done.
a Was the work done on the gas or by the gas?
b Was the thermal energy transferred into the gas zero, 3000 J, higher than 3000 J or lower than 3000 J?
38 The piston of a bicycle pump is pulled out very slowly.
a What happens to the temperature, internal energy and pressure of the gas?
b What assumption did you make?
39 Explain why an adiabatic expansion shown on a pV diagram must be steeper than an isothermal expansion starting at the same point.
40 A sample of an ideal gas expands from 2.23 m3 to 3.47 m3. The gas pressure was originally 3.63 x 105 Pa.
a If the change was isothermal, what was the final pressure of the gas?
b Draw a suitable pV diagram and include these two states.
c Draw a line on the diagram to show how the gas went between these two states.
d Estimate the work done during expansion of the gas.
41 An ideal monatomic gas expands adiabatically from a volume of 6.78 x 10-2 m3 to 9.53 x 10-2 m3. If the initial pressure of the gas was 4.32 x 105 Pa, what was its final pressure?