Question

Which among the following state functions is an extensive property of the system? (1) Temperature (2) Volume (3) Refractive index (4) Viscosity

Short answer

Volume (2)

Step-by-step solution

Understanding Extensive and Intensive Properties

Intensive properties do not depend on the amount of the substance present, while extensive properties do. This characteristic will help identify which property is extensive.

Analyze Temperature

Temperature is an intensive property because it does not change with the amount of substance. For example, the temperature of water remains the same regardless of the quantity.

Analyze Volume

Volume is an extensive property because it depends on the amount of substance. Increasing the amount of substance increases the volume.

Analyze Refractive Index

The refractive index is an intensive property. It remains the same regardless of how much of the substance is present.

Analyze Viscosity

Viscosity is an intensive property. It does not change based on the amount of substance present.

Conclusion

Among the given options, volume is the one that is an extensive property.

Key concepts

Extensive Properties

Extensive properties are characteristics of a system that depend on the amount of matter present. This means they change when the size of the system changes.
For example, consider a pot of water. If you double the amount of water, the volume also doubles because volume is an extensive property.
Other examples of extensive properties include:

• Mass
• Volume
• Total charge
• Total energy

These properties are additive; if you combine two systems, the total value is the sum of the values of each system.

Intensive Properties

Unlike extensive properties, intensive properties do not depend on the amount of matter in a system. These properties remain consistent, no matter how much of the material you have.
For instance, the temperature of the water in a pot does not change if you add more water—it remains constant, making temperature an intensive property.
Other examples of intensive properties include:

• Density
• Boiling Point
• Refractive Index
• Viscosity

These properties are intrinsic to the material and can be very useful for identifying substances.

System Properties

System properties are attributes or characteristics used to describe the state of a system, which can either be intensive or extensive.
When studying a system, it is important to identify which properties are intensive and which are extensive to understand how they will behave under different conditions.
For example, in thermodynamics, you'll often see system properties like:

• Pressure (intensive)
• Temperature (intensive)
• Volume (extensive)
• Mass (extensive)

Recognizing these properties helps in analyzing physical processes and predicting how a system will respond to changes.

Examples of Properties

Let's look at specific examples to clarify the concept further:

• Temperature: This is an intensive property because it does not vary with the amount of substance present.
• Volume: This is an extensive property. Increasing the amount of substance increases the volume accordingly.
• Refractive Index: This is an intensive property, remaining consistent regardless of the substance's quantity.
• Viscosity: Similar to the refractive index, viscosity is an intensive property. It stays the same no matter how much of the material you have.

Understanding these properties helps in solving problems related to thermodynamics, material science, and other physical sciences.
By identifying whether a property is intensive or extensive, you can better predict and control the behavior of a system under various conditions.