The statement "If 0.003 moles of a gas are dissolved in 900 g of water under a pressure of 1 atmosphere , 0.006 moles will be dissolved under a pressure of 2 atmosphere " illustrates

Options

A. Dalton's Law of partial pressures
B. Graham's law
C. Raoult's law
D. Henry's law

Answer

To solve the question, we need to analyze the statement provided and determine which law it illustrates.

### Step-by-Step Solution:

1. **Understanding the Given Information**:
- We have 0.003 moles of a gas dissolved in 900 g of water at a pressure of 1 atmosphere.
- We have 0.006 moles of the same gas dissolved in the same amount of water at a pressure of 2 atmospheres.

2. **Identifying the Relationship**:
- The statement suggests a relationship between the amount of gas dissolved and the pressure applied.
- At 1 atm, 0.003 moles dissolve, and at 2 atm, 0.006 moles dissolve. This indicates that as the pressure increases, the amount of gas that dissolves also increases.

3. **Recalling Relevant Laws**:
- We need to consider various laws of gas solubility:
- **Dalton's Law of Partial Pressure**: Relates to mixtures of gases, not applicable here.
- **Graham's Law of Diffusion**: Relates to the rate of diffusion of gases, not applicable here.
- **Raoult's Law**: Relates to vapor pressure and mole fraction, not applicable here.
- **Henry's Law**: States that the amount of gas dissolved in a liquid is directly proportional to the partial pressure of the gas above the liquid.

4. **Applying Henry's Law**:
- According to Henry's Law, we can express the relationship as:
\[ C \propto P \]
where \( C \) is the concentration (moles of gas dissolved) and \( P \) is the partial pressure of the gas.
- From the data provided:
- At 1 atm: \( C_1 = 0.003 \) moles
- At 2 atm: \( C_2 = 0.006 \) moles
- This shows that doubling the pressure from 1 atm to 2 atm results in doubling the amount of gas dissolved from 0.003 moles to 0.006 moles, which is consistent with Henry's Law.

5. **Conclusion**:
- The statement illustrates **Henry's Law** because it shows that the solubility of the gas in water increases with an increase in pressure.

### Final Answer:
The statement illustrates **Henry's Law**.