Pure covalent double bond is present in

Options

A. Acetylene
B. Carbon dioxide
C. Ethylene
D. Ethane

Explanation

To determine where a pure covalent double bond is present, we need to analyze the types of bonds in the given compounds. A pure covalent bond occurs between atoms of the same element, where the electronegativity difference is zero, resulting in a bond that shares electrons equally.

### Step-by-Step Solution:

1. **Understand the Concept of Pure Covalent Bonds**:
- A pure covalent bond occurs when two identical atoms share electrons equally, leading to no difference in electronegativity (Δx = 0).

2. **Identify the Compounds**:
- The compounds to consider are:
- Acetylene (C2H2)
- Carbon dioxide (CO2)
- Ethylene (C2H4)
- Ethane (C2H6)

3. **Analyze Each Compound**:
- **Acetylene (C2H2)**: Contains a triple bond (C≡C), not a double bond.
- **Carbon Dioxide (CO2)**: Contains double bonds (C=O) between carbon and oxygen, which are different elements (not pure covalent).
- **Ethylene (C2H4)**: Contains a double bond (C=C) between two carbon atoms, which are identical (pure covalent).
- **Ethane (C2H6)**: Contains a single bond (C-C), not a double bond.

4. **Determine the Presence of Pure Covalent Double Bonds**:
- The only compound that has a double bond between similar atoms (carbon and carbon) is Ethylene (C2H4).

5. **Conclusion**:
- Therefore, the compound that contains a pure covalent double bond is Ethylene (C2H4).

### Final Answer:
The pure covalent double bond is present in **Ethylene (C2H4)**.

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