Select correct statement:

Options

A. kinetic energy of `O_(2)` is zero at `O^(@)C`
B. rms velocity of `O_(2)` at `27^(@)C` is `sqrt((3xx8.314xx300)/(32))m//s^(2)`
C. distribution of molecules is very small when `u to 0` or `u to oo`
D. all the statements are correct

Explanation

To solve the question, we need to evaluate each of the provided statements regarding the properties of oxygen (O2) and determine which ones are correct.

### Step 1: Evaluate Statement 1
**Statement 1:** Kinetic energy of O2 is 0 at 0 degrees Celsius.

- The formula for kinetic energy (KE) of a gas is given by:
\[ KE = \frac{3}{2} RT \]
where \( R \) is the universal gas constant (8.314 J/(mol·K)) and \( T \) is the temperature in Kelvin.

- At 0 degrees Celsius, the temperature in Kelvin is:
\[ T = 0 + 273 = 273 \, K \]

- Substituting the values into the kinetic energy formula:
\[ KE = \frac{3}{2} \times 8.314 \times 273 \]

- This calculation will yield a positive value, indicating that the kinetic energy is not zero at 0 degrees Celsius. Therefore, Statement 1 is **not correct**.

### Step 2: Evaluate Statement 2
**Statement 2:** RMS velocity of O2 at 27 degrees Celsius.

- The root mean square (RMS) velocity \( V_{RMS} \) is given by:
\[ V_{RMS} = \sqrt{\frac{3RT}{M}} \]
where \( M \) is the molar mass of the gas (for O2, \( M = 32 \, g/mol \)) and \( T \) is the temperature in Kelvin.

- At 27 degrees Celsius, the temperature in Kelvin is:
\[ T = 27 + 273 = 300 \, K \]

- Substituting the values into the RMS velocity formula:
\[ V_{RMS} = \sqrt{\frac{3 \times 8.314 \times 300}{32}} \]

- Calculating this will give us the RMS velocity of O2 at 27 degrees Celsius. Therefore, Statement 2 is **correct**.

### Step 3: Evaluate Statement 3
**Statement 3:** Distribution of molecules is very small when \( u \) approaches 0 and \( u \) approaches infinity.

- The distribution of molecular speeds follows a Maxwell-Boltzmann distribution. As the speed \( u \) approaches 0, very few molecules have negligible speed, and as \( u \) approaches infinity, very few molecules have extremely high speeds.

- Thus, the distribution of molecules is indeed very small at both extremes (0 and infinity). Therefore, Statement 3 is **correct**.

### Conclusion
After evaluating all statements:
- Statement 1 is **not correct**.
- Statement 2 is **correct**.
- Statement 3 is **correct**.

Thus, the correct statements are **Statement 2 and Statement 3**.