Which of the following statement is correct ?

Options

A. The two oxygen bond length in ozone molecule is different .
B. Ozone can acts a bleaching agent in dry state.
C. Ozone on reaction with Kl solution yields potassium iodate .
D. Ozone oxidises silver to black silver oxide

Explanation

To solve the question regarding which statements about ozone are correct, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement 1:** The two oxygen bond lengths in the ozone molecule are different.

- The structure of ozone (O₃) shows that it has a resonance hybrid with two oxygen-oxygen bonds.
- Due to resonance, both bonds have a partial double bond character.
- Therefore, the bond lengths are identical.

**Conclusion:** This statement is **false**.

### Step 2: Analyze the second statement
**Statement 2:** Ozone can act as a bleaching agent in dry state.

- Ozone can decompose to form nascent oxygen (O) when it dissociates, which is a powerful oxidizing agent.
- This nascent oxygen is responsible for the bleaching action.
- Ozone can indeed act as a bleaching agent without the presence of moisture.

**Conclusion:** This statement is **true**.

### Step 3: Analyze the third statement
**Statement 3:** Ozone on reaction with KI solution kills potassium iodate.

- Ozone reacts with potassium iodide (KI) in the presence of water to produce iodine (I₂) and potassium hydroxide (KOH).
- The reaction does not produce potassium iodate (KIO₃) but rather liberates iodine.

**Conclusion:** This statement is **false**.

### Step 4: Analyze the fourth statement
**Statement 4:** Ozone oxidizes silver to black silver oxide.

- When ozone reacts with silver (Ag), it oxidizes silver to form silver oxide (Ag₂O), which is black in color.
- This reaction confirms that ozone acts as a strong oxidizing agent.

**Conclusion:** This statement is **true**.

### Final Conclusion:
The correct statements are:
- Statement 2: Ozone can act as a bleaching agent in dry state (True).
- Statement 4: Ozone oxidizes silver to black silver oxide (True).

Thus, the correct options are **2 and 4**.

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