The molecules which contain `sigma` bond , `pi` bond and lone pair `1:1:1` ratio :-

Options

A. `C_(2)N_(2)`(Cyanogen )
B. `C_(6)H_(6)` ( Benzene )
C. `C(CN)_(4)` (Tetracyano methane )
D. `C_(3)O_(2)` ( Carbon suboxide )

Answer

To solve the problem of finding a molecule that contains a sigma bond, pi bond, and lone pair in a 1:1:1 ratio, we can follow these steps:

### Step 1: Understand the Definitions
- **Sigma Bond (σ)**: A single bond formed by the head-on overlap of atomic orbitals.
- **Pi Bond (π)**: A bond formed by the side-to-side overlap of p orbitals, typically found in double and triple bonds.
- **Lone Pair**: A pair of valence electrons that are not shared with another atom.

### Step 2: Identify Potential Molecules
We need to find a molecule that has:
- 1 sigma bond
- 1 pi bond
- 1 lone pair

### Step 3: Analyze the Given Molecules
1. **Cyanogen (C2N2)**:
- Structure: C≡N-C≡N
- Sigma Bonds: 3 (one for each C-N bond)
- Pi Bonds: 4 (two for each triple bond)
- Lone Pairs: 2 (one on each nitrogen)
- Ratio: 3:4:2 (not suitable)

2. **Benzene (C6H6)**:
- Structure: C6H6 (cyclic structure)
- Sigma Bonds: 12 (6 C-H and 6 C-C)
- Pi Bonds: 3 (one for each double bond in the resonance structure)
- Lone Pairs: 0
- Ratio: 12:3:0 (not suitable)

3. **Carbon Tetrafluoride (CF4)**:
- Structure: Tetrahedral
- Sigma Bonds: 4 (C-F bonds)
- Pi Bonds: 0
- Lone Pairs: 0
- Ratio: 4:0:0 (not suitable)

4. **Carbon Suboxide (C3O2)**:
- Structure: O=C=C=C=O
- Sigma Bonds: 4 (one for each C-C and C=O bond)
- Pi Bonds: 4 (two for each C=C and C=O bond)
- Lone Pairs: 4 (two on each oxygen)
- Ratio: 4:4:4 (not suitable)

### Step 4: Find the Correct Molecule
After analyzing the above molecules, we find that none of them fit the criteria. However, a molecule that fits the requirement is **Formaldehyde (CH2O)**.

- **Formaldehyde (CH2O)**:
- Structure: H2C=O
- Sigma Bonds: 3 (C-H bonds and C=O bond)
- Pi Bonds: 1 (C=O bond)
- Lone Pairs: 1 (on oxygen)
- Ratio: 3:1:1 (not suitable)

### Conclusion
The correct molecule that fits the 1:1:1 ratio of sigma bonds, pi bonds, and lone pairs is **Carbon Suboxide (C3O2)**.

### Final Answer
The molecule that contains sigma bond, pi bond, and lone pair in a 1:1:1 ratio is **Carbon Suboxide (C3O2)**.

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