Assertion: The diffusion of carbon dioxide is 20 times faster then oxygen.
Reason: It is due to difference in partial pressure as well as solubility of diffusing gases .

Options

A. If both Assertion & Reason are true and the
reason is the correct explanation of the
assertion, then mark (1)
B. If both Assertion & Reason are true but the
reason is not the correct explanation of the
assertion , then mark (2)
C. If Assertion is true statement but Reason is
fakse, then mark (3)
D. If both Assertion and Reason are false
statements, then mark (4)

Answer

To solve the assertion and reason question, we need to analyze both statements carefully.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "The diffusion of carbon dioxide is 20 times faster than oxygen."
- This statement is true. Carbon dioxide (CO2) diffuses more rapidly than oxygen (O2) due to its higher solubility in water and its ability to react with water.

2. **Understanding the Reason**:
- The reason provided is "It is due to the difference in partial pressure as well as solubility of diffusing gases."
- This statement is also true. The diffusion rate of gases is influenced by both their solubility and the partial pressure gradient between the two sides of the membrane.

3. **Analyzing the Relationship**:
- The assertion is true, and the reason is also true.
- Moreover, the reason correctly explains why CO2 diffuses faster than O2. The higher solubility of CO2 compared to O2 and the difference in partial pressures contribute to the faster diffusion rate of CO2.

4. **Conclusion**:
- Both the assertion and the reason are true, and the reason provides a correct explanation for the assertion. Therefore, the correct answer would be that both statements are true, and the reason is the correct explanation for the assertion.

### Final Answer:
Both the assertion and the reason are true, and the reason is the correct explanation for the assertion.

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