Worksheet: Heat and Work

In this worksheet, we will practice defining work, thermal energy, and heat in the context of chemical and physical changes.

Q1:

Which of the following is the best definition of heat?

  • AHeat is the thermal energy of a substance.
  • BHeat is the difference in temperature between a hot and a cold body.
  • CHeat is non-work energy transferred from a hot body to a cold body.
  • DHeat is the temperature of a substance.

Q2:

Which of the following corresponds to a concise statement of the zeroth law of thermodynamics?

  • AThree solid bodies that are all in thermal equilibrium will have the same temperature.
  • BTwo material bodies that are separately in thermal equilibrium with a third body are in thermal equilibrium with each other.
  • CGas molecules in motion tend to stay in motion in the absence of applied forces.
  • DMolecules can be treated as noninteracting point masses when contained in gaseous samples at very low pressures and number densities.

Q3:

What is the name of the process in which there is no thermal energy exchanged between a system and its surroundings?

  • AAn isobaric process
  • BIsochoric process
  • CAn adiabatic process
  • DAn isothermal process
  • EA diathermic process

Q4:

Consider a process in which a sample of water vapor expands reversibly and adiabatically from a state in which its pressure is 8 . 0 × 1 0 bar and its volume is 0.5 dm3 to a state in which its volume is 3 dm3. If it is assumed that the water vapor behaves as an ideal gas (with respect to its 𝑃 𝑉 𝑇 properties) and that the ratio of its 𝐶 and 𝐶 heat-capacity quantities is given by 𝛾 = 𝐶 𝐶 = 1 . 3 , what will the final pressure of the vapor sample be?

  • A 5.83 bar
  • B 0.307 bar
  • C 0.821 bar
  • D 7 . 7 9 × 1 0 bar

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.