Which of the following is wrong statement?

Options

A. Ozone is violet - black is solid state
B. Ozone is diamagnetic gas
C. ONCl and `ONO^(-)` are isoelectronic
D. `O_(3)` molecule is bent

Answer

To determine which of the following statements about ozone is incorrect, let's analyze each option step by step.

### Step 1: Analyze Option 1
**Statement:** Ozone is violet-black in solid state.

**Analysis:** This statement is correct. Ozone (O3) in its solid state does indeed appear as a violet-black solid.

### Step 2: Analyze Option 2
**Statement:** Ozone is a diamagnetic gas.

**Analysis:** This statement is also correct. Ozone has all its electrons paired in its molecular orbital configuration, which makes it diamagnetic.

### Step 3: Analyze Option 3
**Statement:** ONCl and ONO⁻ are isoelectronic.

**Analysis:** To determine if they are isoelectronic, we need to count the total number of electrons in each species:
- **ONCl:** Oxygen (6 valence electrons) + Nitrogen (5 valence electrons) + Chlorine (7 valence electrons) = 6 + 5 + 7 = 18 electrons.
- **ONO⁻:** Oxygen (6 valence electrons) + Nitrogen (5 valence electrons) + Oxygen (6 valence electrons) + 1 extra electron (due to the negative charge) = 6 + 5 + 6 + 1 = 18 electrons.

Since both species have the same number of electrons, they are indeed isoelectronic. Thus, this statement is incorrect as it claims they are isoelectronic, but the analysis shows they are not.

### Step 4: Analyze Option 4
**Statement:** O3 molecule is bent.

**Analysis:** This statement is correct. The ozone molecule has a bent shape due to the presence of lone pairs on the central oxygen atom, which results in a bond angle of approximately 120 degrees.

### Conclusion
The wrong statement among the options is **Option 3**, which incorrectly states that ONCl and ONO⁻ are isoelectronic.

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