Distinguish between a closed system and an open system.

Explanation

To distinguish between a closed system and an open system, we can follow these steps:

### Step 1: Define a Closed System
A closed system is defined as a physical system that allows the transfer of energy (in the form of heat or work) across its boundary but does not allow the transfer of matter.

### Step 2: Provide an Example of a Closed System
Consider a closed container filled with water. If the water is heated to a temperature of 100 degrees Celsius while the outside temperature is 25 degrees Celsius, heat will transfer from the water to the surrounding air. However, the water itself does not leave the container; only the heat energy crosses the boundary. This illustrates the characteristics of a closed system.

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