Understanding Thermodynamic Systems and Examples

Thermodynamic systems are classified based on their interactions with their surroundings, specifically regarding the exchange of energy and matter.

Types of Thermodynamic Systems

Let's define the three main types of thermodynamic systems:

• Open System: This system can exchange both energy (like heat and work) and matter with its surroundings.
• Closed System: This system can exchange energy (like heat and work) with its surroundings, but not matter. The amount of substance within the system remains constant.
• Isolated System: This system cannot exchange either energy or matter with its surroundings. It is completely cut off from the environment.

Analyzing the Examples

Now let's look at the provided examples and determine which type of system they represent:

• Example I: The gas sealed within the cylinder of a spark-ignition engine. During certain phases of the engine cycle (like combustion or expansion stroke when valves are closed), the mass of the gas inside the cylinder is fixed. However, heat is transferred (due to combustion) and work is done (as the piston moves). Since energy is exchanged but matter is not, this represents a Closed System.
• Example II: Liquid nitrogen stored in a sealed and insulated container. The container is sealed, preventing matter exchange. It is also insulated, designed to minimize heat transfer (energy exchange). While perfect isolation is difficult in practice, this example best fits the description of an Isolated System.
• Example III: A car radiator. Coolant flows through the radiator, entering and leaving. This involves the exchange of matter. Heat is also transferred from the hot coolant to the surrounding air. Since both matter and energy are exchanged, this is an Open System.

Matching Systems with Examples

Based on the analysis, we can match the thermodynamic systems with their correct examples:

Therefore, the correct match is A - III, B - I, C - II.