Acetylene upon ozonolysis gives

Answer

To solve the question of what acetylene gives upon ozonolysis, we can follow these steps:

### Step-by-Step Solution:

1. **Identify Acetylene Structure**:
Acetylene is a simple alkyne with the formula C₂H₂, which can be represented as H-C≡C-H.

2. **Understanding Ozonolysis**:
Ozonolysis is a reaction where ozone (O₃) reacts with alkenes or alkynes to cleave the double or triple bonds, forming ozonides.

3. **Reaction of Acetylene with Ozone**:
When acetylene (C₂H₂) reacts with ozone (O₃), it forms an ozonide. The reaction can be represented as:
\[ \text{C}_2\text{H}_2 + \text{O}_3 \rightarrow \text{C}_2\text{H}_2\text{O}_3 \text{ (ozonide)} \]

4. **Hydrolysis of Ozonide**:
The ozonide formed is then hydrolyzed in the presence of a reducing agent like zinc (Zn) and water (H₂O). This hydrolysis breaks down the ozonide to yield aldehydes.
\[ \text{C}_2\text{H}_2\text{O}_3 + \text{H}_2\text{O} \xrightarrow{\text{Zn}} \text{2 CHO} \]

5. **Final Product**:
The hydrolysis of the ozonide leads to the formation of glyoxal (CHO-CHO), which is a dialdehyde. Therefore, the final product of the ozonolysis of acetylene is glyoxal.

### Final Answer:
Acetylene upon ozonolysis gives glyoxal (CHO-CHO).

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