In thermodynamics, which type of system can exchange both energy and matter with its surroundings?

An open system is defined as one that can exchange both energy and matter with its surroundings. This means that both heat transfer and mass transfer can occur, allowing for interactions that can significantly influence the system's thermodynamic properties. For instance, consider a boiling pot of water: steam (which is matter) leaves the pot into the air, and energy in the form of heat is also imparted to the surrounding environment. This characteristic enables open systems to dynamically respond to changes in their environment, making them fundamental to many physical and chemical processes.

In contrast, a closed system can exchange energy, such as heat, but not matter with its surroundings. An example of a closed system might be a sealed container of gas that can absorb or release heat but cannot allow gas to escape or enter. An isolated system is one that can neither exchange energy nor matter with its environment, such as a thermos that keeps both its contents and thermal energy enclosed. Lastly, an equilibrium system refers to a state where the macroscopic properties remain constant over time; it doesn't define the ability of the system to exchange energy or matter but rather its condition at a specific moment. Thus, distinguishing the characteristics of open systems highlights their versatility in exchanging both energy and matter with the environment.