`O_(3)` reacts with `CH_(2)=CH_(2)` to form ozonide. On hydrolysis it forms __________.

Options

A. ethylene oxide
B. HCHO
C. ethylene glycol
D. ethyl alcohol

Answer

To solve the problem, we need to understand the reaction between ozone (O₃) and ethylene (CH₂=CH₂) and what products are formed during the hydrolysis of the ozonide.

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this reaction are ozone (O₃) and ethylene (CH₂=CH₂).

2. **Ozonolysis Reaction**: When ozone reacts with ethylene, it undergoes a process called ozonolysis. In this reaction, the double bond of ethylene is cleaved, and an ozonide is formed. The reaction can be summarized as follows:
\[ \text{CH}_2=\text{CH}_2 + \text{O}_3 \rightarrow \text{Ozonide} \]

3. **Structure of the Ozonide**: The ozonide formed from this reaction is a cyclic compound that contains an ozonide functional group. The structure can be represented as:
\[ \text{Ozonide: R-O-O-R'} \]
where R and R' are the ethyl groups from ethylene.

4. **Hydrolysis of Ozonide**: The next step involves the hydrolysis of the ozonide. Hydrolysis means reacting the ozonide with water (H₂O). During hydrolysis, the ozonide is converted into carbonyl compounds. In the case of ethylene, the ozonide will yield two molecules of formaldehyde (HCHO).

5. **Final Product**: Thus, the final product after hydrolysis of the ozonide formed from ethylene is:
\[ \text{2 HCHO (formaldehyde)} \]

### Conclusion:
The answer to the question is that on hydrolysis, the ozonide formed from the reaction of O₃ with CH₂=CH₂ yields formaldehyde.

### Answer:
**Formaldehyde (HCHO)**

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