Question

\(C_p / C_v\) for noble gases is

• A. 1.66
• B. 1.43
• C. 1.80
• D. 1.33

Hint:

For diatomic gases at room temperature, \(\gamma = 7/5 = 1.4\). For triatomic gases, \(\gamma = 4/3 = 1.33\).

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
\(C_p/C_v\) (also denoted as \(\gamma\)) is the ratio of specific heats. For monatomic gases, \(\gamma = 5/3\).
Step 2: Detailed Explanation:
Noble gases are monatomic. For a monatomic ideal gas, degrees of freedom = 3 (translational only). \(C_v = \frac{3}{2}R\), \(C_p = C_v + R = \frac{5}{2}R\). \(\gamma = \frac{C_p}{C_v} = \frac{5/2}{3/2} = \frac{5}{3} = 1.666... \approx 1.66\).
Step 3: Final Answer:
\(C_p/C_v\) for noble gases is 1.66, option (A).