Which of the following pairs contains only intensive properties?
Show Hint
A quick way to remember:
If a property changes when the size of the system changes, it is \textbf{extensive}.
If it remains the same regardless of system size, it is \textbf{intensive}.
Examples:
Extensive → Mass, Volume
Intensive → Temperature, Pressure, Density
Step 1: Understanding the Question:
The question requires us to identify the pair of physical properties that are classified as "intensive".
In thermodynamics, properties are categorized as either intensive or extensive.
- Intensive properties are independent of the mass or size of the system (e.g., temperature, pressure, density).
- Extensive properties depend on the amount of substance in the system (e.g., mass, volume, energy). Step 2: Detailed Explanation:
We will analyze each option to determine if both properties in the pair are intensive. Option (A) Mass, Volume:
- Mass is an extensive property because it directly depends on the amount of matter.
- Volume is also an extensive property as it changes with the size of the system.
Thus, this pair is incorrect. Option (B) Density, Temperature:
- Density (\( \text{mass}/\text{volume} \)) is an intensive property. If you take a larger sample, both mass and volume increase, but their ratio (density) remains constant.
- Temperature is an intensive property. A small cup of boiling water and a large pot of boiling water both have the same temperature (100°C at standard pressure).
Since both are intensive properties, this pair is correct. Option (C) Volume, Pressure:
- Volume is an extensive property.
- Pressure is an intensive property.
Since this pair contains an extensive property, it is incorrect. Option (D) Mass, Density:
- Mass is an extensive property.
- Density is an intensive property.
Since this pair contains an extensive property, it is incorrect. Step 3: Final Answer:
The only pair where both properties are intensive is Density and Temperature.
