Ozone is prepared by passing silent electric discharge through oxygen. In this reaction

Options

A. energy is given out
B. energy is absorbed
C. oxygen is dissociated into atom
D. oxygen is loaded with energy.

Explanation

To solve the question regarding the preparation of ozone by passing silent electric discharge through oxygen, we will analyze the process step by step.

### Step 1: Understanding the Reaction
When silent electric discharge is passed through oxygen (O₂), it leads to the formation of ozone (O₃). The reaction can be represented as:
\[ 3 O_2 \rightarrow 2 O_3 \]

### Step 2: Energy Change in the Reaction
In this process, energy is required to break the bonds in the O₂ molecules. This energy is supplied by the electric discharge. Therefore, the reaction is not spontaneous and requires energy input.

### Step 3: Classifying the Reaction
Since energy is absorbed during the formation of ozone from oxygen, this reaction is classified as an endothermic reaction. In an endothermic reaction, the enthalpy change (ΔH) is positive, indicating that energy is absorbed from the surroundings.

### Step 4: Evaluating the Options
Now, we evaluate the options provided in the question:
1. Energy is given out - This is incorrect as the reaction absorbs energy.
2. Energy is absorbed - This is correct as the reaction is endothermic.
3. Oxygen is dissociated into atoms - This is incorrect; oxygen remains as O₂ and forms O₃.
4. Oxygen is loaded with energy - This is misleading; while energy is provided, it is not accurate to say oxygen is "loaded" with energy.

### Conclusion
Based on the analysis, the correct answer is that energy is absorbed during the reaction, which corresponds to option 2.

### Final Answer
**Energy is absorbed. (Option 2)**

---