Consider Three one -litre flasks labeled A,B and C filled with the gases `NO,NO_(2),` and `N_(2)O,` respectively, each at 1 atm and 273 K. In which flask do the molecules have the highest average kinetic energy?

Options

A. Flask C
B. All are the same
C. Flask A
D. None

Explanation

To solve the problem of determining which flask has the highest average kinetic energy of the gas molecules, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Relationship Between Kinetic Energy and Temperature**:
The average kinetic energy (KE) of gas molecules is given by the formula:
\[ KE_{\text{average}} = \frac{3}{2} RT \]
where \( R \) is the universal gas constant and \( T \) is the absolute temperature in Kelvin.

2. **Identify the Conditions for Each Flask**:
According to the problem, all three flasks (A, B, and C) contain gases (NO, NO₂, and N₂O, respectively) at the same conditions:
- Volume: 1 liter
- Pressure: 1 atm
- Temperature: 273 K

3. **Evaluate the Temperature**:
Since the temperature \( T \) is the same for all three flasks (273 K), we can conclude that the average kinetic energy of the gas molecules in each flask will be the same.

4. **Conclusion**:
Since the average kinetic energy depends solely on temperature and all three flasks have the same temperature, the average kinetic energy of the molecules in flasks A, B, and C will be identical. Therefore, there is no flask with a higher average kinetic energy; they are all equal.

### Final Answer:
The average kinetic energy of the molecules is the same in all three flasks (A, B, and C) because they are at the same temperature of 273 K.

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