The environment and the system together make up the universe in thermodynamic studies.
Energy can be transferred between a system and its environment in the form of heat or work.
The boundary separating the system from the environment can be fixed or movable, depending on whether work is done.
In an isolated system, there is no interaction with the surrounding environment (no exchange of energy or matter).
Changes in a system's internal energy are influenced by interactions with its environment.
Review Questions
What constitutes the 'environment' in a thermodynamic problem?
How does energy transfer occur between a system and its environment?
What happens at the boundary between a thermodynamic system and its environment?
Related terms
System: A specific portion of matter or space chosen for study, separated from its surroundings by boundaries.
Surroundings: Another term used interchangeably with 'environment,' it includes everything external to the thermodynamic system.
$\Delta U$ (Change in Internal Energy): The difference in internal energy of a system, which depends on heat exchanged and work done with/to the environment.