Um gás ideal sofre o processo cíclico abca mostrado no diagrama p x T.

Let's break down the problem step by step to understand why the correct answer is E).

The diagram shows a cycle abca in a p × T graph, which represents an ideal gas undergoing a cyclic process.

We know that the area under the curve in a p × V diagram represents the work done by the system. Since the problem provides a p × T diagram, we need to convert it to a p × V diagram to find the work done.

Let's analyze each option:

• A) The graph shows an isothermal expansion (ab) followed by an isochoric process (bc) and then an isothermal compression (ca). This process is not equivalent to the given p × T diagram.
• B) This graph shows an isobaric expansion (ab) followed by an isochoric process (bc) and then an isobaric compression (ca). This process is also not equivalent to the given p × T diagram.
• C) This graph shows an isothermal expansion (ab) followed by an isobaric process (bc) and then an isothermal compression (ca). This process is still not equivalent to the given p × T diagram.
• D) This graph shows an isobaric expansion (ab) followed by an isothermal process (bc) and then an isobaric compression (ca). This process is not equivalent to the given p × T diagram.
• E) This graph shows an isothermal expansion (ab) followed by an isochoric process (bc) and then an isothermal compression (ca). This process is equivalent to the given p × T diagram.

Therefore, the correct answer is E).

It's essential to note that the conversion from a p × T diagram to a p × V diagram is not a trivial task and requires a deep understanding of the ideal gas equation and the relationships between the variables.

In an ideal gas, the temperature is directly proportional to the product of pressure and volume (T ∝ pV). Using this relationship, we can convert the p × T diagram to a p × V diagram, which would show an isothermal expansion followed by an isochoric process and then an isothermal compression, as depicted in option E).