What is characteristic of an isothermal process?

An isothermal process is defined as a thermodynamic process that occurs at a constant temperature. In such a scenario, while heat can be exchanged with the surroundings, the temperature of the system does not change throughout the process. This is particularly significant in the context of an ideal gas, where the relationship between pressure, volume, and temperature is described by the ideal gas law. According to this law, if the temperature remains constant while a gas expands or compresses, the pressure and volume will adjust in such a way that their product remains constant.

While pressure, volume, and internal energy may change during an isothermal process for an ideal gas, the critical aspect is that the temperature remains constant. Internal energy is particularly dependent on temperature for ideal gases; therefore, if the temperature is constant, the internal energy does not change either.

Understanding the implications of an isothermal process lays the groundwork for analyzing more complex thermodynamic processes and the relationships between the different state variables like temperature, pressure, and volume.