Which law states that "product of volume and pressure at constant temperature is constant for a dry gas of given mass".

Options

A. Charles.s law
B. Boyle.s law
C. Henry.s law
D. Dalton.s law

Answer

To solve the question, we need to identify which gas law states that the product of volume and pressure at constant temperature is constant for a dry gas of a given mass.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for a specific gas law that relates pressure and volume at a constant temperature for a dry gas.

2. **Identifying the Laws**: We have four options:
- Charles's Law
- Boyle's Law
- Henry's Law
- Dalton's Law

3. **Reviewing Boyle's Law**:
- Boyle's Law states that for a given mass of gas at constant temperature, the pressure (P) of the gas is inversely proportional to its volume (V). This can be mathematically expressed as:
\[ P \propto \frac{1}{V} \quad \text{or} \quad PV = K \]
- Here, K is a constant value for a specific amount of gas at a constant temperature.

4. **Conclusion**: Since Boyle's Law explicitly states that the product of pressure and volume is constant when the temperature is held constant, we can conclude that the correct answer to the question is **Boyle's Law**.

### Final Answer:
The law that states that the product of volume and pressure at constant temperature is constant for a dry gas of a given mass is **Boyle's Law**.

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