Assertion : The ratio `C_(P)// C_(upsilon)` for a diatomic gas is more than that for a monoatomic gas.
Reason : The moleculess of a monoatomic gas have more degrees of freedom than those of a diatomic gas.

Options

A. If both assertion and reason are true and reason is the correct explanation os assertion.
B. If both assertion and reason are true but reason is not be correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To solve the question, we need to analyze the assertion and reason provided regarding the specific heat capacities of monoatomic and diatomic gases.

### Step 1: Understanding the Assertion
The assertion states that the ratio \( \frac{C_P}{C_V} \) for a diatomic gas is more than that for a monoatomic gas.

### Step 2: Specific Heat Capacities of Monoatomic Gas
For a monoatomic gas:
- The degrees of freedom \( f = 3 \) (only translational motion).
- The specific heat at constant volume \( C_V = \frac{3}{2} R \).
- The specific heat at constant pressure \( C_P = C_V + R = \frac{3}{2} R + R = \frac{5}{2} R \).

Now, we can find the ratio:
\[ \frac{C_P}{C_V} = \frac{\frac{5}{2} R}{\frac{3}{2} R} = \frac{5}{3} \]

### Step 3: Specific Heat Capacities of Diatomic Gas
For a diatomic gas:
- The degrees of freedom \( f = 5 \) (3 translational + 2 rotational).
- The specific heat at constant volume \( C_V = \frac{5}{2} R \).
- The specific heat at constant pressure \( C_P = C_V + R = \frac{5}{2} R + R = \frac{7}{2} R \).

Now, we can find the ratio:
\[ \frac{C_P}{C_V} = \frac{\frac{7}{2} R}{\frac{5}{2} R} = \frac{7}{5} \]

### Step 4: Comparing the Ratios
Now we compare the ratios:
- For monoatomic gas: \( \frac{C_P}{C_V} = \frac{5}{3} \)
- For diatomic gas: \( \frac{C_P}{C_V} = \frac{7}{5} \)

Since \( \frac{7}{5} > \frac{5}{3} \), the assertion is correct.

### Step 5: Understanding the Reason
The reason states that the molecules of a monoatomic gas have more degrees of freedom than those of a diatomic gas. This statement is incorrect because:
- Monoatomic gases have 3 degrees of freedom.
- Diatomic gases have 5 degrees of freedom.

### Conclusion
- The assertion is true: \( \frac{C_P}{C_V} \) for a diatomic gas is indeed more than that for a monoatomic gas.
- The reason is false: Monoatomic gases do not have more degrees of freedom than diatomic gases.

Thus, the final conclusion is:
- Assertion: True
- Reason: False