P6 Thermodynamics

What is the first law of thermodynamics?

• Energy cannot be created or destroyed, only transferred or transformed.

• The entropy of an isolated system always decreases.

• The internal energy of a system is equal to its pressure multiplied by volume.

• Heat transfer occurs from colder objects to hotter objects spontaneously.

Which of the following is an extensive property in thermodynamics?

• Temperature

• Pressure

• Volume

• Density

What is the SI unit of entropy?

• Joule (J)

• Pascal (Pa)

• Joule per Kelvin (J/K)

• Kelvin per Joule (K/J)

Which thermodynamic process occurs at constant volume?

• Isothermal

• Isochoric

• Isobaric

• Adiabatic

What happens to the temperature of an ideal gas during an adiabatic expansion?

• It remains constant.

• It increases.

• It decreases.

• It depends on the heat added.

If the temperature of a gas increases while the volume remains constant, what happens to its pressure?

• It remains the same.

• It decreases.

• It increases.

• It first increases and then decreases.

In an isobaric process, how does heat energy affect a gas system?

• It only increases the temperature.

• It only increases the volume.

• It does not change the system's state.

• It increases both temperature and volume.

Why does an insulated container help maintain the internal energy of a system?

• It prevents work from being done on the system.

• It allows the system to expand freely.

• It minimizes heat exchange with the surroundings.

• It increases the entropy of the system.

Which of the following best describes entropy in a spontaneous process?

• Entropy always decreases.

• Entropy remains constant.

• Entropy increases.

• Entropy can increase or decrease depending on pressure.

Two identical metal rods, one at 100°C and the other at 20°C, are placed in contact. What happens to their temperatures over time?

• The hotter rod cools down while the cooler rod warms up until equilibrium is reached.

• The temperature difference remains unchanged.

• The hotter rod gets hotter while the cooler rod gets cooler.

• Heat does not transfer between the rods.