Thermodynamics quiz

The concept of temperature is based on the:

The first law of thermodynamics is a form of conservation of:

In an isothermal process for an ideal gas, the change in internal energy is:

In an adiabatic process:

In an isochoric process, the work done is:

In a cyclic process, the change in internal energy is:

The area under a P-V curve gives the:

The internal energy of an ideal gas depends on its:

According to the second law, heat cannot flow spontaneously from:

The free expansion of a gas into a vacuum is:

Distinguish between heat and work as modes of energy transfer. (2 marks)

What is a quasi-static process? (2 marks)

Why does a bicycle pump become warm when used rapidly? (2 marks)

Explain why the specific heat at constant pressure is greater than that at constant volume. (2 marks)

What are state variables? Give two examples. (2 marks)

Explain why the air coming out of a burst tyre feels cool. (2 marks)

Write the equation for an adiabatic process of an ideal gas. (2 marks)

State the Kelvin-Planck or Clausius statement of the second law. (2 marks)

What is a reversible process? Why is it an idealisation? (2 marks)

What are extensive and intensive variables? Give one example of each. (2 marks)

A cylinder contains 3 mol of hydrogen at STP. Find the heat needed to raise its temperature by 20 degrees Celsius at constant volume, taking Cv = (5/2)R. (3 marks)

A gas does 300 J of work while its internal energy decreases by 100 J. Find the heat absorbed or released. (3 marks)

In a cyclic process, a gas absorbs 800 J of heat. Find the net work done. (3 marks)

2 mol of an ideal gas are compressed isothermally at 300 K to half their volume. Find the work done on the gas. (3 marks)

A gas expands at a constant pressure of 2 x 10^5 Pa from 1 L to 3 L while absorbing 1000 J of heat. Find the change in its internal energy. (3 marks)

Read the passage and answer the questions. A cyclist pumps air into a tyre quickly, and the pump barrel becomes warm. (i) Name the process occurring in the pump. (ii) Why does the temperature rise? (iii) Write the first law for this process. (5 marks)

Read the passage and answer the questions. A gas in a cylinder with a movable piston is heated slowly at constant pressure. (i) Name the process. (ii) Write the expression for the work done. (iii) Is all the heat used to raise the internal energy? Explain. (5 marks)

Read the passage and answer the questions. A sealed rigid container of gas is placed in sunlight. (i) Name the process. (ii) How much work is done by the gas? (iii) Where does all the absorbed heat go? (5 marks)

Read the passage and answer the questions. A student studies a gas taken through a closed cycle on a P-V diagram. (i) What is the change in internal energy over one cycle? (ii) How is the net work found from the diagram? (iii) If the cycle runs clockwise, is net work done by or on the gas? (5 marks)

Read the passage and answer the questions. A cup of hot coffee cools in a room, but the room never spontaneously heats the coffee. (i) Which law explains this? (ii) Is the cooling process reversible? (iii) Give another example of an irreversible process. (5 marks)

Explain thermal equilibrium and the zeroth law of thermodynamics, and show how it leads to the concept of temperature. (6 marks)

State and explain the first law of thermodynamics. Apply it to isothermal, adiabatic, isochoric and isobaric processes. (6 marks)

Derive the relation Cp - Cv = R for an ideal gas using the first law. (6 marks)

Explain thermodynamic state variables and the equation of state, and distinguish between quasi-static and non-quasi-static processes. (6 marks)

State the second law of thermodynamics. Explain reversible and irreversible processes with examples, and give reasons why real processes are irreversible. (6 marks)