1.1. A sample of an ideal gas is contained in a rigid container enclosed by a piston, as shown in Fig. 1.1.

Fig. 1.1

The work done has a negative value.

State and explain the direction of the piston's motion.

1.2. The gas is perfectly insulated during this process.

Write an algebraic expression relating change in internal energy and work done.

1.3. Describe the change in temperature of the gas.

Explain your answer.