70 Date Name CONCEPTUAL Physics PRACTICE PAGE Chapter 14 Gases Gas Pressure 1. A Principle Difference Between A Liquid And A Gas Is That When Aliquid Is Under Pressure, Its Volume Increases) (Decreases) Doesn't Change Noticeably PHYS165 And Its Density S16 Increases (Decrease Doesn't Change
The correct answer and explanation is:
Correct Answer:
- When a liquid is under pressure, its volume decreases.
- When a liquid is under pressure, its density increases.
Explanation:
The behavior of liquids and gases under pressure is governed by fundamental principles of fluid mechanics and molecular behavior.
- Liquids Under Pressure:
- Unlike gases, liquids are incompressible, meaning they do not change volume significantly when pressure is applied. However, under extreme pressure, a very small decrease in volume can be observed.
- The molecules in a liquid are already closely packed together, so when pressure is applied, the intermolecular spaces reduce slightly, leading to a decrease in volume.
- Since density is defined as mass per unit volume (ρ=mV\rho = \frac{m}{V}), a decrease in volume results in an increase in density.
- Gases Under Pressure:
- Gases, on the other hand, are highly compressible because their molecules are far apart and can be forced closer together.
- When pressure is applied to a gas, its volume decreases significantly, following Boyle’s Law (P1V1=P2V2P_1 V_1 = P_2 V_2), which states that at constant temperature, pressure and volume are inversely proportional.
- As the volume of a gas decreases, its density increases, as the same number of gas molecules occupy a smaller space.
- Key Difference Between Liquids and Gases:
- A liquid resists compression due to strong intermolecular forces, while a gas can be compressed easily because of the large spaces between molecules.
- This is why gases are used in pneumatic systems, while liquids are used in hydraulic systems, where incompressibility is an advantage.
Thus, the correct answer is:
- Volume decreases when a liquid is under pressure.
- Density increases when a liquid is under pressure.
Now, I’ll generate an image illustrating this concept.
Here is an educational diagram comparing the behavior of a liquid and a gas under pressure. Let me know if you need any modifications or explanations!
